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Sample records for biologically relevant concentrations

  1. Biological effects of environmentally relevant concentrations of the pharmaceutical Triclosan in the marine mussel Perna perna (Linnaeus, 1758)

    Energy Technology Data Exchange (ETDEWEB)

    Sanzi Cortez, Fernando, E-mail: lecotox@unisanta.br [Instituto de Pesquisas Energeticas e Nucleares IPEN-CNEN/SP, 05508-000 Sao Paulo, SP (Brazil); Laboratorio de Ecotoxicologia, Universidade Santa Cecilia, 11045-907 Santos, SP (Brazil); Dias Seabra Pereira, Camilo [Laboratorio de Ecotoxicologia, Universidade Santa Cecilia, 11045-907 Santos, SP (Brazil); Instituto do Mar, Universidade Federal de Sao Paulo, 11030-400 Santos, SP (Brazil); Ramos Santos, Aldo Ramos [Laboratorio de Ecotoxicologia, Universidade Santa Cecilia, 11045-907 Santos, SP (Brazil); Cesar, Augusto; Choueri, Rodrigo Brasil [Laboratorio de Ecotoxicologia, Universidade Santa Cecilia, 11045-907 Santos, SP (Brazil); Instituto do Mar, Universidade Federal de Sao Paulo, 11030-400 Santos, SP (Brazil); Martini, Gisela de Assis [Laboratorio de Ecotoxicologia, Universidade Santa Cecilia, 11045-907 Santos, SP (Brazil); Bohrer-Morel, Maria Beatriz [Instituto de Pesquisas Energeticas e Nucleares IPEN-CNEN/SP, 05508-000 Sao Paulo, SP (Brazil)

    2012-09-15

    Triclosan (5-Chloro-2-(2,4-dichlorophenoxy) phenol) is an antibacterial compound widely employed in pharmaceuticals and personal care products. Although this emerging compound has been detected in aquatic environments, scarce information is found on the effects of Triclosan to marine organisms. The aim of this study was to evaluate the toxicity of a concentration range of Triclosan through fertilization assay (reproductive success), embryo-larval development assay (early life stage) and physiological stress (Neutral Red Retention Time assay - NRRT) (adult stage) in the marine sentinel organism Perna perna. The mean inhibition concentrations for fertilization (IC{sub 50} = 0.490 mg L{sup -1}) and embryo-larval development (IC{sub 50} = 0.135 mg L{sup -1}) tests were above environmental relevant concentrations (ng L{sup -1}) given by previous studies. Differently, significant reduction on NRRT results was found at 12 ng L{sup -1}, demonstrating the current risk of the continuous introduction of Triclosan into aquatic environments, and the need of ecotoxicological studies oriented by the mechanism of action of the compound. - Highlights: Black-Right-Pointing-Pointer Triclosan causes biological adverse effects at environmental relevant concentrations. Black-Right-Pointing-Pointer Mechanisms of action oriented assays were more sensitive to detect biological damages. Black-Right-Pointing-Pointer Currently there is environmental risks concerned Triclosan in aquatic ecosystems. - Triclosan causes biological adverse effects at environmentally relevant concentrations.

  2. Biological effects of environmentally relevant concentrations of the pharmaceutical Triclosan in the marine mussel Perna perna (Linnaeus, 1758)

    International Nuclear Information System (INIS)

    Sanzi Cortez, Fernando; Dias Seabra Pereira, Camilo; Ramos Santos, Aldo Ramos; Cesar, Augusto; Choueri, Rodrigo Brasil; Martini, Gisela de Assis; Bohrer-Morel, Maria Beatriz

    2012-01-01

    Triclosan (5-Chloro-2-(2,4-dichlorophenoxy) phenol) is an antibacterial compound widely employed in pharmaceuticals and personal care products. Although this emerging compound has been detected in aquatic environments, scarce information is found on the effects of Triclosan to marine organisms. The aim of this study was to evaluate the toxicity of a concentration range of Triclosan through fertilization assay (reproductive success), embryo-larval development assay (early life stage) and physiological stress (Neutral Red Retention Time assay - NRRT) (adult stage) in the marine sentinel organism Perna perna. The mean inhibition concentrations for fertilization (IC 50 = 0.490 mg L −1 ) and embryo-larval development (IC 50 = 0.135 mg L −1 ) tests were above environmental relevant concentrations (ng L −1 ) given by previous studies. Differently, significant reduction on NRRT results was found at 12 ng L −1 , demonstrating the current risk of the continuous introduction of Triclosan into aquatic environments, and the need of ecotoxicological studies oriented by the mechanism of action of the compound. - Highlights: ► Triclosan causes biological adverse effects at environmental relevant concentrations. ► Mechanisms of action oriented assays were more sensitive to detect biological damages. ► Currently there is environmental risks concerned Triclosan in aquatic ecosystems. - Triclosan causes biological adverse effects at environmentally relevant concentrations.

  3. Other relevant biological papers

    International Nuclear Information System (INIS)

    Shimizu, M.

    1989-01-01

    A considerable number of CRESP-relevant papers concerning deep-sea biology and radioecology have been published. It is the purpose of this study to call attention to them. They fall into three general categories. The first is papers of general interest. They are mentioned only briefly, and include text references to the global bibliography at the end of the volume. The second are papers that are not only mentioned and referenced, but for various reasons are described in abstract form. The last is a list of papers compiled by H.S.J. Roe specifically for this volume. They are listed in bibliographic form, and are also included in the global bibliography at the end of the volume

  4. Biology relevant to space radiation

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1996-01-01

    The biological effects of the radiations to which mankind on earth are exposed are becoming known with an increasing degree of detail. This knowledge is the basis of the estimates of risk that, in turn, fosters a comprehensive and evolving radiation protection system. The substantial body of information has been, and is being, applied to questions about the biological effects of radiation is space and the associated risk estimates. The purpose of this paper is not to recount all the biological effect of radiation but to concentrate on those that may occur as a result from exposure to the radiations encountered in space. In general, the biological effects of radiation in space are the same as those on earth. However, the evidence that the effects on certain tissues by the heaviest-charged particles can be interpreted on the basis of our knowledge about other high-LET radiation is equivocal. This specific question will be discussed in greater detail later. It is important to point out the that there are only limited data about the effects on humans of two components of the radiations in space, namely protons and heavy ions. Thus predictions of effects on space crews are based on experimental systems exposed on earth at rates and fluences that are higher than those in space and one the effects of gamma or x rays with estimates of the equivalent doses using quality factors

  5. Beta-defensin-2 protein is a serum biomarker for disease activity in psoriasis and reaches biologically relevant concentrations in lesional skin.

    Directory of Open Access Journals (Sweden)

    Patrick A M Jansen

    Full Text Available BACKGROUND: Previous studies have extensively documented antimicrobial and chemotactic activities of beta-defensins. Human beta-defensin-2 (hBD-2 is strongly expressed in lesional psoriatic epidermis, and recently we have shown that high beta-defensin genomic copy number is associated with psoriasis susceptibility. It is not known, however, if biologically and pathophysiologically relevant concentrations of hBD-2 protein are present in vivo, which could support an antimicrobial and proinflammatory role of beta-defensins in lesional psoriatic epidermis. METHODOLOGY/PRINCIPAL FINDINGS: We found that systemic levels of hBD-2 showed a weak but significant correlation with beta defensin copy number in healthy controls but not in psoriasis patients with active disease. In psoriasis patients but not in atopic dermatitis patients, we found high systemic hBD-2 levels that strongly correlated with disease activity as assessed by the PASI score. Our findings suggest that systemic levels in psoriasis are largely determined by secretion from involved skin and not by genomic copy number. Modelling of the in vivo epidermal hBD-2 concentration based on the secretion rate in a reconstructed skin model for psoriatic epidermis provides evidence that epidermal hBD-2 levels in vivo are probably well above the concentrations required for in vitro antimicrobial and chemokine-like effects. CONCLUSIONS/SIGNIFICANCE: Serum hBD-2 appears to be a useful surrogate marker for disease activity in psoriasis. The discrepancy between hBD-2 levels in psoriasis and atopic dermatitis could explain the well known differences in infection rate between these two diseases.

  6. Biology relevant to space radiation

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1997-01-01

    There are only very limited data on the health effects to humans from the two major components of the radiations in space, namely protons and heavy ions. As a result, predictions of the accompanying effects must be based either on (1) data generated through studies of experimental systems exposed on earth at rates and fluences higher than those in space, or (2) extrapolations from studies of gamma and x rays. Better information is needed about the doses, dose rates, and the energy and LET spectra of the radiations at the organ level that are anticipated to be encountered during extended space missions. In particular, there is a need for better estimates of the relationship between radiation quality and biological effects. In the case of deterministic effects, it is the threshold that is important. The possibility of the occurrence of a large solar particle event (SPE) requires that such effects be considered during extended space missions. Analyses suggest, however, that it is feasible to provide sufficient shielding so as to reduce such effects to acceptable levels, particularly if the dose rates can be limited. If these analyses prove correct, the primary biological risks will be the stochastic effects (latent cancer induction). The contribution of one large SPE to the risk of stochastic effects while undesirable will not be large in comparison to the potential total dose on a mission of long duration

  7. The Integrin Receptor in Biologically Relevant Bilayers

    DEFF Research Database (Denmark)

    Kalli, Antreas C.; Róg, Tomasz; Vattulainen, Ilpo

    2017-01-01

    /talin complex was inserted in biologically relevant bilayers that resemble the cell plasma membrane containing zwitterionic and charged phospholipids, cholesterol and sphingolipids to study the dynamics of the integrin receptor and its effect on bilayer structure and dynamics. The results of this study...... demonstrate the dynamic nature of the integrin receptor and suggest that the presence of the integrin receptor alters the lipid organization between the two leaflets of the bilayer. In particular, our results suggest elevated density of cholesterol and of phosphatidylserine lipids around the integrin....../talin complex and a slowing down of lipids in an annulus of ~30 Å around the protein due to interactions between the lipids and the integrin/talin F2–F3 complex. This may in part regulate the interactions of integrins with other related proteins or integrin clustering thus facilitating signal transduction...

  8. Gregory Bateson's relevance to current molecular biology

    DEFF Research Database (Denmark)

    Bruni, Luis Emilio

    2008-01-01

    in a developmental pathway. Being a central figure in the development of cybernetic theory he collaborated with a range of researchers from the life sciences who were innovating their own disciplines by introducing cybernetic concepts in their particular fields and disciplines. In the light of this, it should...... not come as a surprise today to realize how the general ideas that he was postulating for the study of communication systems in biology fit so well with the astonishing findings of current molecular biology, for example in the field of cellular signal transduction networks. I guess this is the case due...

  9. Silk-polypyrrole biocompatible actuator performance under biologically relevant conditions

    Science.gov (United States)

    Hagler, Jo'elen; Peterson, Ben; Murphy, Amanda; Leger, Janelle

    Biocompatible actuators that are capable of controlled movement and can function under biologically relevant conditions are of significant interest in biomedical fields. Previously, we have demonstrated that a composite material of silk biopolymer and the conducting polymer polypyrrole (PPy) can be formed into a bilayer device that can bend under applied voltage. Further, these silk-PPy composites can generate forces comparable to human muscle (>0.1 MPa) making them ideal candidates for interfacing with biological tissues. Here silk-PPy composite films are tested for performance under biologically relevant conditions including exposure to a complex protein serum and biologically relevant temperatures. Free-end bending actuation performance, current response, force generation and, mass degradation were investigated . Preliminary results show that when exposed to proteins and biologically relevant temperatures, these silk-PPy composites show minimal degradation and are able to generate forces and conduct currents comparable to devices tested under standard conditions. NSF.

  10. Dilution thermodynamics of the biologically relevant cation mixtures

    International Nuclear Information System (INIS)

    Kaczyński, Marek; Borowik, Tomasz; Przybyło, Magda; Langner, Marek

    2014-01-01

    Graphical abstract: - Highlights: • Dilution energetics of Ca 2+ can be altered by the aqueous phase ionic composition. • Dissipated heat upon Ca 2+ dilution is drastically reduced in the K + presence. • Reduction of the enthalpy change upon Ca 2+ dilution is K + concentration dependent. • The cooperativity of Ca 2+ hydration might be of great biological relevance providing a thermodynamic argument for the specific ionic composition of the intracellular environment. - Abstract: The ionic composition of intracellular space is rigorously controlled by a variety of processes consuming large quantities of energy. Since the energetic efficiency is an important evolutional criterion, therefore the ion fluxes within the cell should be optimized with respect to the accompanying energy consumption. In the paper we present the experimental evidence that the dilution enthalpies of the biologically relevant ions; i.e. calcium and magnesium depend on the presence of monovalent cations; i.e. sodium and potassium. The heat flow generated during the dilution of ionic mixtures was measured with the isothermal titration calorimetry. When calcium was diluted together with potassium the dilution enthalpy was drastically reduced as the function of the potassium concentration present in the solution. No such effect was observed when the potassium ions were substituted with sodium ones. When the dilution of magnesium was investigated the dependence of the dilution enthalpy on the accompanying monovalent cation was much weaker. In order to interpret experimental evidences the ionic cluster formation is postulated. The specific organization of such cluster should depend on ions charges, sizes and organization of the hydration layers

  11. Value-Relevance of Biological Assets under IFRS

    OpenAIRE

    Rute Gonçalves; Patrícia Lopes

    2015-01-01

    Using 389 firm-year observations of listed firms worldwide in 27 countries that adopted International Financial Reporting Standards (IFRS) until 2010, for the period 2011-2013, the purpose of this paper is to examine the value-relevance of fair value accounting of biological assets. In order to operationalize it as the book value’s ability to explain market equity value, this study adjusts the Ohlson model. The results support that recognized biological assets are value-relevant. After includ...

  12. Biological relevance and synthesis of C-substituted morpholine derivatives

    NARCIS (Netherlands)

    Wijtmans, R.; Vink, M.K.S.; Schoemaker, H.E.; Delft, F.L. van; Blaauw, R.H.; Rutjes, F.P.J.T.

    2004-01-01

    C-Functionalized morpholines are found in a variety of natural products and biologically active compounds, but have also for other reasons been applied in organic synthesis. This review deals with the biological relevance of C-substituted morpholines, their synthesis and important applications in

  13. Hands-on-Entropy, Energy Balance with Biological Relevance

    Science.gov (United States)

    Reeves, Mark

    2015-03-01

    Entropy changes underlie the physics that dominates biological interactions. Indeed, introductory biology courses often begin with an exploration of the qualities of water that are important to living systems. However, one idea that is not explicitly addressed in most introductory physics or biology textbooks is important contribution of the entropy in driving fundamental biological processes towards equilibrium. From diffusion to cell-membrane formation, to electrostatic binding in protein folding, to the functioning of nerve cells, entropic effects often act to counterbalance deterministic forces such as electrostatic attraction and in so doing, allow for effective molecular signaling. A small group of biology, biophysics and computer science faculty have worked together for the past five years to develop curricular modules (based on SCALEUP pedagogy). This has enabled students to create models of stochastic and deterministic processes. Our students are first-year engineering and science students in the calculus-based physics course and they are not expected to know biology beyond the high-school level. In our class, they learn to reduce complex biological processes and structures in order model them mathematically to account for both deterministic and probabilistic processes. The students test these models in simulations and in laboratory experiments that are biologically relevant such as diffusion, ionic transport, and ligand-receptor binding. Moreover, the students confront random forces and traditional forces in problems, simulations, and in laboratory exploration throughout the year-long course as they move from traditional kinematics through thermodynamics to electrostatic interactions. This talk will present a number of these exercises, with particular focus on the hands-on experiments done by the students, and will give examples of the tangible material that our students work with throughout the two-semester sequence of their course on introductory

  14. Clinical relevance and biology of circulating tumor cells

    Science.gov (United States)

    2011-01-01

    Most breast cancer patients die due to metastases, and the early onset of this multistep process is usually missed by current tumor staging modalities. Therefore, ultrasensitive techniques have been developed to enable the enrichment, detection, isolation and characterization of disseminated tumor cells in bone marrow and circulating tumor cells in the peripheral blood of cancer patients. There is increasing evidence that the presence of these cells is associated with an unfavorable prognosis related to metastatic progression in the bone and other organs. This review focuses on investigations regarding the biology and clinical relevance of circulating tumor cells in breast cancer. PMID:22114869

  15. The complexity of DNA damage: relevance to biological consequences

    International Nuclear Information System (INIS)

    Ward, J.F.

    1994-01-01

    Ionizing radiation causes both singly and multiply damaged sites in DNA when the range of radical migration is limited by the presence of hydroxyl radical scavengers (e.g. within cells). Multiply damaged sites are considered to be more biologically relevant because of the challenges they present to cellular repair mechanisms. These sites occur in the form of DNA double-strand breaks (dsb) but also as other multiple damages that can be converted to dsb during attempted repair. The presence of a dsb can lead to loss of base sequence information and/or can permit the two ends of a break to separate and rejoin with the wrong partner. (Multiply damaged sites may also be the biologically relevant type of damage caused by other agents, such as UVA, B and/or C light, and some antitumour antibiotics). The quantitative data available from radiation studies of DNA are shown to support the proposed mechanisms for the production of complex damage in cellular DNA, i.e. via scavengable and non-scavengable mechanisms. The yields of complex damages can in turn be used to support the conclusion that cellular mutations are a consequence of the presence of these damages within a gene. (Author)

  16. Biclustering methods: biological relevance and application in gene expression analysis.

    Directory of Open Access Journals (Sweden)

    Ali Oghabian

    Full Text Available DNA microarray technologies are used extensively to profile the expression levels of thousands of genes under various conditions, yielding extremely large data-matrices. Thus, analyzing this information and extracting biologically relevant knowledge becomes a considerable challenge. A classical approach for tackling this challenge is to use clustering (also known as one-way clustering methods where genes (or respectively samples are grouped together based on the similarity of their expression profiles across the set of all samples (or respectively genes. An alternative approach is to develop biclustering methods to identify local patterns in the data. These methods extract subgroups of genes that are co-expressed across only a subset of samples and may feature important biological or medical implications. In this study we evaluate 13 biclustering and 2 clustering (k-means and hierarchical methods. We use several approaches to compare their performance on two real gene expression data sets. For this purpose we apply four evaluation measures in our analysis: (1 we examine how well the considered (biclustering methods differentiate various sample types; (2 we evaluate how well the groups of genes discovered by the (biclustering methods are annotated with similar Gene Ontology categories; (3 we evaluate the capability of the methods to differentiate genes that are known to be specific to the particular sample types we study and (4 we compare the running time of the algorithms. In the end, we conclude that as long as the samples are well defined and annotated, the contamination of the samples is limited, and the samples are well replicated, biclustering methods such as Plaid and SAMBA are useful for discovering relevant subsets of genes and samples.

  17. Purified deoxynivalenol or feed restriction reduces mortality in rainbow trout, Oncorhynchus mykiss (Walbaum), with experimental bacterial coldwater disease but biologically relevant concentrations of deoxynivalenol do not impair the growth of Flavobacterium psychrophilum.

    Science.gov (United States)

    Ryerse, I A; Hooft, J M; Bureau, D P; Hayes, M A; Lumsden, J S

    2015-09-01

    Diets containing deoxynivalenol (DON) were fed to rainbow trout Oncorhynchus mykiss (Walbaum) for 4 weeks followed by experimental infection (intraperitoneal) with Flavobacterium psychrophilum (4.1 × 10(6) colony-forming units [CFU] mL(-1) ). Mortality of rainbow trout fed either 6.4 mg kg(-1) DON or trout pair-fed the control diet was significantly reduced (P trout fed the control diet to apparent satiation (trout were fed one of three experimental diets; a control diet, a diet produced with corn naturally contaminated with DON (3.3 mg kg(-1) DON) or a diet containing purified DON (3.8 mg kg(-1) ); however, these fish were not experimentally infected. The presence of DON resulted in significant reduction (P trout fed diets containing purified DON (3.8 mg kg(-1) ) was significantly higher (P < 0.05) at 35 day post-exposure compared with controls. The antimicrobial activity of DON was examined by subjecting F. psychrophilum in vitro to serial dilutions of the chemical. Complete inhibition occurred at a concentration of 75 mg L(-1) DON, but no effect was observed below this concentration (0-30 mg L(-1) ). © 2014 John Wiley & Sons Ltd.

  18. Arbitrary protein−protein docking targets biologically relevant interfaces

    Directory of Open Access Journals (Sweden)

    Martin Juliette

    2012-05-01

    Full Text Available Abstract Background Protein-protein recognition is of fundamental importance in the vast majority of biological processes. However, it has already been demonstrated that it is very hard to distinguish true complexes from false complexes in so-called cross-docking experiments, where binary protein complexes are separated and the isolated proteins are all docked against each other and scored. Does this result, at least in part, reflect a physical reality? False complexes could reflect possible nonspecific or weak associations. Results In this paper, we investigate the twilight zone of protein-protein interactions, building on an interesting outcome of cross-docking experiments: false complexes seem to favor residues from the true interaction site, suggesting that randomly chosen partners dock in a non-random fashion on protein surfaces. Here, we carry out arbitrary docking of a non-redundant data set of 198 proteins, with more than 300 randomly chosen "probe" proteins. We investigate the tendency of arbitrary partners to aggregate at localized regions of the protein surfaces, the shape and compositional bias of the generated interfaces, and the potential of this property to predict biologically relevant binding sites. We show that the non-random localization of arbitrary partners after protein-protein docking is a generic feature of protein structures. The interfaces generated in this way are not systematically planar or curved, but tend to be closer than average to the center of the proteins. These results can be used to predict biological interfaces with an AUC value up to 0.69 alone, and 0.72 when used in combination with evolutionary information. An appropriate choice of random partners and number of docking models make this method computationally practical. It is also noted that nonspecific interfaces can point to alternate interaction sites in the case of proteins with multiple interfaces. We illustrate the usefulness of arbitrary docking

  19. Arbitrary protein−protein docking targets biologically relevant interfaces

    International Nuclear Information System (INIS)

    Martin, Juliette; Lavery, Richard

    2012-01-01

    Protein-protein recognition is of fundamental importance in the vast majority of biological processes. However, it has already been demonstrated that it is very hard to distinguish true complexes from false complexes in so-called cross-docking experiments, where binary protein complexes are separated and the isolated proteins are all docked against each other and scored. Does this result, at least in part, reflect a physical reality? False complexes could reflect possible nonspecific or weak associations. In this paper, we investigate the twilight zone of protein-protein interactions, building on an interesting outcome of cross-docking experiments: false complexes seem to favor residues from the true interaction site, suggesting that randomly chosen partners dock in a non-random fashion on protein surfaces. Here, we carry out arbitrary docking of a non-redundant data set of 198 proteins, with more than 300 randomly chosen "probe" proteins. We investigate the tendency of arbitrary partners to aggregate at localized regions of the protein surfaces, the shape and compositional bias of the generated interfaces, and the potential of this property to predict biologically relevant binding sites. We show that the non-random localization of arbitrary partners after protein-protein docking is a generic feature of protein structures. The interfaces generated in this way are not systematically planar or curved, but tend to be closer than average to the center of the proteins. These results can be used to predict biological interfaces with an AUC value up to 0.69 alone, and 0.72 when used in combination with evolutionary information. An appropriate choice of random partners and number of docking models make this method computationally practical. It is also noted that nonspecific interfaces can point to alternate interaction sites in the case of proteins with multiple interfaces. We illustrate the usefulness of arbitrary docking using PEBP (Phosphatidylethanolamine binding

  20. Dealing with immunogenicity of biologicals: assessment and clinical relevance

    NARCIS (Netherlands)

    Wolbink, Gerrit J.; Aarden, Lucien A.; Dijkmans, B. A. C.

    2009-01-01

    PURPOSE OF REVIEW: In the last decade, biologicals revolutionized rheumatology. An increasing number of patients benefit from biotherapeuticals. However, some patients do not respond to treatment and others lose their response after a certain time. Immunogenicity is one of the factors linked to

  1. Single Molecule Fluorescence: from Physical Fascination to Biological Relevance

    OpenAIRE

    Segers-Nolten, Gezina M.J.

    2003-01-01

    Confocal fluorescence microscopy is particularly well-known from the beautiful images that have been obtained with this technique from cells. Several cellular components could be nicely visualized simultaneously by staining them with different fluorophores. Not only for ensemble applications but also in single molecule research confocal fluorescence microscopy became a popular technique. In this thesis the possibilities are shown to study a complicated biological process, which is Nucleotide ...

  2. Streptococcus pyogenes biofilms – formation, biology,and clinical relevance

    Directory of Open Access Journals (Sweden)

    Tomas eFiedler

    2015-02-01

    Full Text Available Streptococcus pyogenes (group A streptococci, GAS is an exclusive human bacterial pathogen. The virulence potential of this species is tremendous. Interactions with humans range from asymptomatic carriage over mild and superficial infections of skin and mucosal membranes up to systemic purulent toxic-invasive disease manifestations. Particularly the latter are a severe threat for predisposed patients and lead to significant death tolls worldwide. This places GAS among the most important Gram-positive bacterial pathogens. Many recent reviews have highlighted the GAS repertoire of virulence factors, regulators and regulatory circuits/networks that enable GAS to colonize the host and to deal with all levels of the host immune defense. This covers in vitro and in vivo studies, including animal infection studies based on mice and more relevant, macaque monkeys. It is now appreciated that GAS, like many other bacterial species, do not necessarily exclusively live in a planktonic lifestyle. GAS is capable of microcolony and biofilm formation on host cells and tissues. We are now beginning to understand that this feature significantly contributes to GAS pathogenesis. In this review we will discuss the current knowledge on GAS biofilm formation, the biofilm-phenotype associated virulence factors, regulatory aspects of biofilm formation, the clinical relevance, and finally contemporary treatment regimens and future treatment options.

  3. Biology and relevance of human acute myeloid leukemia stem cells.

    Science.gov (United States)

    Thomas, Daniel; Majeti, Ravindra

    2017-03-23

    Evidence of human acute myeloid leukemia stem cells (AML LSCs) was first reported nearly 2 decades ago through the identification of rare subpopulations of engrafting cells in xenotransplantation assays. These AML LSCs were shown to reside at the apex of a cellular hierarchy that initiates and maintains the disease, exhibiting properties of self-renewal, cell cycle quiescence, and chemoresistance. This cancer stem cell model offers an explanation for chemotherapy resistance and disease relapse and implies that approaches to treatment must eradicate LSCs for cure. More recently, a number of studies have both refined and expanded our understanding of LSCs and intrapatient heterogeneity in AML using improved xenotransplant models, genome-scale analyses, and experimental manipulation of primary patient cells. Here, we review these studies with a focus on the immunophenotype, biological properties, epigenetics, genetics, and clinical associations of human AML LSCs and discuss critical questions that need to be addressed in future research. © 2017 by The American Society of Hematology.

  4. Inactivation of the antibacterial and cytotoxic properties of silver ions by biologically relevant compounds.

    Directory of Open Access Journals (Sweden)

    Geraldine Mulley

    Full Text Available There has been a recent surge in the use of silver as an antimicrobial agent in a wide range of domestic and clinical products, intended to prevent or treat bacterial infections and reduce bacterial colonization of surfaces. It has been reported that the antibacterial and cytotoxic properties of silver are affected by the assay conditions, particularly the type of growth media used in vitro. The toxicity of Ag+ to bacterial cells is comparable to that of human cells. We demonstrate that biologically relevant compounds such as glutathione, cysteine and human blood components significantly reduce the toxicity of silver ions to clinically relevant pathogenic bacteria and primary human dermal fibroblasts (skin cells. Bacteria are able to grow normally in the presence of silver nitrate at >20-fold the minimum inhibitory concentration (MIC if Ag+ and thiols are added in a 1:1 ratio because the reaction of Ag+ with extracellular thiols prevents silver ions from interacting with cells. Extracellular thiols and human serum also significantly reduce the antimicrobial activity of silver wound dressings Aquacel-Ag (Convatec and Acticoat (Smith & Nephew to Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli in vitro. These results have important implications for the deployment of silver as an antimicrobial agent in environments exposed to biological tissue or secretions. Significant amounts of money and effort have been directed at the development of silver-coated medical devices (e.g. dressings, catheters, implants. We believe our findings are essential for the effective design and testing of antimicrobial silver coatings.

  5. Colloidal stability of silver nanoparticles in biologically relevant conditions

    International Nuclear Information System (INIS)

    MacCuspie, Robert I.

    2011-01-01

    Understanding the colloidal stability of nanoparticles (NPs) plays a key role in phenomenological interpretation of toxicological experiments, particularly if single NPs or their aggregates or agglomerates determine the dominant experimental result. This report examines a variety of instrumental techniques for surveying the colloidal stability of aqueous suspensions of silver nanoparticles (AgNPs), including atomic force microscopy, dynamic light scattering, and colorimetry. It was found that colorimetry can adequately determine the concentration of single AgNPs that remained in solution if morphological information about agglomerates is not required. The colloidal stability of AgNPs with various surface capping agents and in various solvents ranging from cell culture media to different electrolytes of several concentrations, and in different pH conditions was determined. It was found that biocompatible bulky capping agents, such as bovine serum albumin or starch, that provided steric colloidal stabilization, as opposed to purely electrostatic stabilization such as with citrate AgNPs, provided better retention of single AgNPs in solution over a variety of conditions for up to 64 h of observation.

  6. Rethinking the central dogma: noncoding RNAs are biologically relevant.

    Science.gov (United States)

    Robinson, Victoria L

    2009-01-01

    Non-coding RNAs (ncRNAs) are a large class of functional molecules with over 100 unique classes described to date. ncRNAs are diverse in terms of their function and size. A relatively new class of small ncRNA, called microRNAs (miRNA), have received a great deal of attention in the literature in recent years. miRNAs are endogenously encoded gene families that demonstrate striking evolutionary conservation. miRNAs serve essential and diverse physiological functions such as differentiation and development, proliferation, maintaining cell type phenotypes, and many others. The discovery and ongoing investigation of miRNAs is part of a revolution in biology that is changing the basic concepts of gene expression and RNA functionality. A single miRNA can participate in controlling the expression of up to several hundred protein-coding genes by interacting with mRNAs, generally in 3' untranslated regions. Our new and developing understanding of miRNAs, and other ncRNAs, promises to lead to significant contributions to medicine. Specifically, miRNAs are likely to serve as the basis for novel therapies and diagnostic tools.

  7. Biological relevance of human papillomaviruses in vulvar cancer.

    Science.gov (United States)

    Halec, Gordana; Alemany, Laia; Quiros, Beatriz; Clavero, Omar; Höfler, Daniela; Alejo, Maria; Quint, Wim; Pawlita, Michael; Bosch, Francesc X; de Sanjose, Silvia

    2017-04-01

    The carcinogenic role of high-risk human papillomavirus (HR-HPV) types in the increasing subset of vulvar intraepithelial neoplasia and vulvar cancer in young women has been established. However, the actual number of vulvar cancer cases attributed to HPV is still imprecisely defined. In an attempt to provide a more precise definition of HPV-driven vulvar cancer, we performed HPV-type-specific E6*I mRNA analyses available for 20 HR-/possible HR (pHR)-HPV types, on tissue samples from 447 cases of vulvar cancer. HPV DNA genotyping was performed using SPF10-LiPA 25 assay due to its high sensitivity in formalin-fixed paraffin-embedded tissues. Data on p16 INK4a expression was available for comparative analysis via kappa statistics. The use of highly sensitive assays covering the detection of HPV mRNA in a broad spectrum of mucosal HPV types resulted in the detection of viral transcripts in 87% of HPV DNA+ vulvar cancers. Overall concordance between HPV mRNA+ and p16 INK4a upregulation (strong, diffuse immunostaining in >25% of tumor cells) was 92% (K=0.625, 95% confidence interval (CI)=0.531-0.719). Among these cases, 83% were concordant pairs of HPV mRNA+ and p16 INK4a + and 9% were concordant pairs of HPV mRNA- and p16 INK4a -. Our data confirm the biological role of HR-/pHR-HPV types in the great majority of HPV DNA+ vulvar cancers, resulting in an HPV-attributable fraction of at least 21% worldwide. Most HPV DNA+ vulvar cancers were associated with HPV16 (85%), but a causative role for other, less frequently occurring mucosal HPV types (HPV26, 66, 67, 68, 70 and 73) was also confirmed at the mRNA level for the first time. These findings should be taken into consideration for future screening options as HPV-associated vulvar preneoplastic lesions have increased in incidence in younger women and require different treatment than vulvar lesions that develop from rare autoimmune-related mechanisms in older women.

  8. Beyond arousal and valence: the importance of the biological versus social relevance of emotional stimuli

    OpenAIRE

    Sakaki, Michiko; Niki, N.; Mather, M.

    2012-01-01

    The present study addressed the hypothesis that emotional stimuli relevant to survival or reproduction (biologically emotional stimuli) automatically affect cognitive processing (e.g., attention, memory), while those relevant to social life (socially emotional stimuli) require elaborative processing to modulate attention and memory. Results of our behavioral studies showed that (1) biologically emotional images hold attention more strongly than do socially emotional images, (2) memory for bio...

  9. Transport of Fluorescently Labeled Hydroxyapatite Nanoparticles in Saturated Granular Media at Environmentally Relevant Concentrations of Surfactants

    Science.gov (United States)

    Little is known about the mobility of engineered nanoparticles (ENPs) in granular media at environmentally relevant concentration of surfactant, which represents a critical knowledge gap in employing ENPs for in-situ remediation of contaminated groundwater. In this study, transpo...

  10. Maximum concentrations at work and maximum biologically tolerable concentration for working materials 1991

    International Nuclear Information System (INIS)

    1991-01-01

    The meaning of the term 'maximum concentration at work' in regard of various pollutants is discussed. Specifically, a number of dusts and smokes are dealt with. The valuation criteria for maximum biologically tolerable concentrations for working materials are indicated. The working materials in question are corcinogeneous substances or substances liable to cause allergies or mutate the genome. (VT) [de

  11. Altered pairing behaviour and reproductive success in white ibises exposed to environmentally relevant concentrations of methylmercury.

    Science.gov (United States)

    Frederick, Peter; Jayasena, Nilmini

    2011-06-22

    Methylmercury (MeHg) is the most biologically available and toxic form of mercury, and can act as a powerful teratogen, neurotoxin and endocrine disruptor in vertebrates. However, mechanisms of endocrine impairment and net effects on demography of biota are poorly understood. Here, we report that experimental exposure of an aquatic bird over 3 years to environmentally relevant dietary MeHg concentrations (0.05-0.3 ppm wet weight) resulted in dose-related increases in male-male pairing behaviour (to 55% of males), and decreases in egg productivity (to 30%). Dosed males showed decreased rates of key courtship behaviours, and were approached less by courting females in comparison to control males. Within dosed groups, homosexual males showed a similar reduction when compared with dosed heterosexual males. We found an average 35 per cent decrease in fledgling production in high-dose birds over the study duration. These results are of interest because (i) MeHg exposure is experimentally tied to demographically important reproductive deficits, (ii) these effects were found at low, chronic exposure levels commonly experienced by wildlife, and (iii) effects on reproductive behaviour and sexual preference mediated by endocrine disruption represent a novel and probably under-reported mechanism by which contaminants may influence wild populations of birds.

  12. Early stress responses in Atlantic salmon (Salmo salar) exposed to environmentally relevant concentrations of uranium

    International Nuclear Information System (INIS)

    Song You; Salbu, Brit; Heier, Lene Sørlie; Teien, Hans-Christian; Lind, Ole-Christian; Oughton, Deborah; Petersen, Karina; Rosseland, Bjørn Olav; Skipperud, Lindis; Tollefsen, Knut Erik

    2012-01-01

    Uranium (U) is a naturally occurring heavy metal widely used in many military and civil applications. Uranium contamination and the associated potential adverse effects of U on the aquatic environment have been debated during recent years. In order to understand the effect and mode of action (MoA) of U in vivo, juvenile Atlantic salmon (Salmo salar) were exposed to 0.25 mg/L, 0.5 mg/L and 1.0 mg/L waterborne depleted uranyl acetate, respectively, in a static system for 48 h. The U concentrations in the gill and liver were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and the resulting biological effects were determined by a combination of analysis of gene expression and micronuclei formation. The hepatic transcriptional level of 12 biomarker genes from four stress–response categories, including oxidative stress (γ-glutamyl cysteine synthetase (GCS), glutathione reductase (GR), glutathione peroxidase (GPx)), DNA damage and repair (P53, cyclin-dependent kinase inhibitor 1 (P21), growth arrest and DNA damage-inducible gene gamma (Gadd45G), proliferating cell nuclear antigen (PCNA), Rad51), apoptosis (Bcl2-associated X protein (BAX), Bcl-x, Caspase 6A,) and protein degradation (Ubiquitin) were evaluated by quantitative real-time polymerase chain reaction (q-rtPCR). The results clearly showed accumulation of U in the gill and liver with increasing concentrations of U in the exposure water. The effects of U on differential hepatic gene expression also occurred in a concentration-dependent manner, although deviations from ideal concentration–response relationships were observed at the highest U concentration (1.0 mg/L). All the genes tested were found to be up-regulated by U while no significant micronuclei formation was identified. The results suggest that U may cause oxidative stress in fish liver at concentrations greater than 0.25 mg/L, giving rise to clear induction of several toxicologically relevant biomarker genes, although no significant

  13. Studies on influence of biological factors on concentration of radionuclides

    International Nuclear Information System (INIS)

    Anon.

    1974-01-01

    Biological factors influencing the concentration of radionuclides were studied from the points of uptake through digestive tract, food as pathways, and metabolic activities. The uptake of radionuclides by marine fishes through digestive tract was determined by whole body counter. 137 Cs, 65 Zn, 131 I, 54 Mn, 60 Co, 85 Sr, and 144 Ce were used as tracers and was given with solid feed. The feed given was excreated 24 to 48 hours later in small of middle sized fishes, and 20 to 48 hours later in large sized fishes. The uptake rate of 137 Cs and 65 Zn was high absorption of 20 to 80 per cent, that of 131 I, 60 Co and 54 Mn was not remarkable, and that of 85 Sr and 144 Ce was low absorption. The biological concentration of 137 Cs through pathways of food. In fishes taking up radionuclides through contaminated food, concentration factor increased in accordance with contamination level. In addition, radionuclides with small uptake but delayed excretion and those with high concentration rate could be the factors to decide the concentration factors of marine organisms. In order to study the relationship between metabolic activities and concentration, the uptake of one-year old fishes and adult fishes, and fishes fed and those non-fed were compared. One-year fishes took up large amount of 85 Sr during short period, however, concentration by metabolism in adult fishes was slow. Comparing feeding group and non-feeding group, the former showed 85 Sr concentration factor of 1.5 to 2 times that of the later, and the later showed 137 Cs concentration factor of 2 to 4 times that of the former. However, both uptake and excretion were rapid suggesting that taking food activated the metabolism of substances. (Kanao, N.)

  14. A study of ruthenium complexes of some biologically relevant a-N ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 112; Issue 3. A study of ruthenium complexes of some biologically relevant ∙ -N-heterocyclic ... Author Affiliations. P Sengupta1 S Ghosh1. Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Calcutta 700 032, India ...

  15. Beyond arousal and valence: the importance of the biological versus social relevance of emotional stimuli.

    Science.gov (United States)

    Sakaki, Michiko; Niki, Kazuhisa; Mather, Mara

    2012-03-01

    The present study addressed the hypothesis that emotional stimuli relevant to survival or reproduction (biologically emotional stimuli) automatically affect cognitive processing (e.g., attention, memory), while those relevant to social life (socially emotional stimuli) require elaborative processing to modulate attention and memory. Results of our behavioral studies showed that (1) biologically emotional images hold attention more strongly than do socially emotional images, (2) memory for biologically emotional images was enhanced even with limited cognitive resources, but (3) memory for socially emotional images was enhanced only when people had sufficient cognitive resources at encoding. Neither images' subjective arousal nor their valence modulated these patterns. A subsequent functional magnetic resonance imaging study revealed that biologically emotional images induced stronger activity in the visual cortex and greater functional connectivity between the amygdala and visual cortex than did socially emotional images. These results suggest that the interconnection between the amygdala and visual cortex supports enhanced attention allocation to biological stimuli. In contrast, socially emotional images evoked greater activity in the medial prefrontal cortex (MPFC) and yielded stronger functional connectivity between the amygdala and MPFC than did biological images. Thus, it appears that emotional processing of social stimuli involves elaborative processing requiring frontal lobe activity.

  16. Determination of 18O concentrations in microsamples of biological fluids

    International Nuclear Information System (INIS)

    Cohen, D.D.; Bradshaw, S.D.; Bradshaw, F.J.

    1990-01-01

    The 18 O(p, α) 15 N reaction has been developed for the analysis of microsamples of biological fluids containing 18 O-enriched water. Samples as small as 50 μl have been used. Well characterized Ta 2 O 5 targets were prepared from these fluids and irradiated with several hundred nA of protons from the 3 MV Van de Graaff at Lucas Heights. The broad (47 keV) 846 kV resonance in this reaction was used to measure 18 O concentrations down to natural backgrounds (0.2 at.%) in a few minutes of accelerator running time. Concentrations of 18 O from 0 to 5 at.% were measured in body fluids in small Australian lizards directly after doping with 18 O-enriched water and then again after several days of roaming around in their natural desert environments. The changes in these levels were related to the metabolic rates of these animals. (orig.)

  17. Assessment of health status of oysters (Crassostreagigas) exposed to environmentally relevant concentrations of Ag and Cu in brackish waters

    Science.gov (United States)

    Rementeria, Ane; Mikolaczyk, Mathilde; Peña, Ainhize; Lanceleur, Laurent; Blanc, Gérard; Soto, Manu; Schäfer, Jörg; Zaldibar, Beñat

    2017-12-01

    Human activities have altered estuarine environments leading to increased presence of different pollutants including metals. Although the implementation of new environmental policies has caused a considerable decrease in trace metal concentrations in estuaries around the Bay of Biscay, some elements such as copper (Cu) and silver (Ag) are still present in relatively high concentrations. Oysters have been widely used in environmental biomonitoring programs as sentinel organisms. Oysters Crassostrea gigas from an uncontaminated estuary were exposed to sublethal, environmentally relevant concentrations of Cu (2000 ng Cu/L) and Ag (500 ng Ag/L) during 14 days in brackish water (S = 18). A battery of cell and tissue level (exposure) biomarkers at different levels of biological complexity was applied and integrated into the Integrative Biological Response (IBR) index including: metallothionein contents, intralysosomal metal accumulation, digestive gland atrophy and digestive gland tissue integrity. Condition Index (CI) was incorporated into the IBR index as a complementary parameter that reflects the general physiological condition of oysters (organism level). Results indicated an increase in intralysosomal metal accumulation after 7 and 14 days of exposure to Ag together with an increase in the digestive epithelium atrophy and lipofuscin content after 7 days of exposure to Ag. The responses detected with the aid of biomarkers integrated in the IBR index showed higher toxicity in oysters exposed to Ag, inducing the clear onset of detoxification processes which also occurred, to a lower extent, in Cu-exposed oysters.

  18. Acoustic fine structure may encode biologically relevant information for zebra finches.

    Science.gov (United States)

    Prior, Nora H; Smith, Edward; Lawson, Shelby; Ball, Gregory F; Dooling, Robert J

    2018-04-18

    The ability to discriminate changes in the fine structure of complex sounds is well developed in birds. However, the precise limit of this discrimination ability and how it is used in the context of natural communication remains unclear. Here we describe natural variability in acoustic fine structure of male and female zebra finch calls. Results from psychoacoustic experiments demonstrate that zebra finches are able to discriminate extremely small differences in fine structure, which are on the order of the variation in acoustic fine structure that is present in their vocal signals. Results from signal analysis methods also suggest that acoustic fine structure may carry information that distinguishes between biologically relevant categories including sex, call type and individual identity. Combined, our results are consistent with the hypothesis that zebra finches can encode biologically relevant information within the fine structure of their calls. This study provides a foundation for our understanding of how acoustic fine structure may be involved in animal communication.

  19. Breath acetone concentration; biological variability and the influence of diet

    International Nuclear Information System (INIS)

    Španěl, Patrik; Dryahina, Kseniya; Rejšková, Alžběta; Chippendale, Thomas W E; Smith, David

    2011-01-01

    Previous measurements of acetone concentrations in the exhaled breath of healthy individuals and the small amount of comparable data for individuals suffering from diabetes are briefly reviewed as a prelude to the presentation of new data on the sporadic and wide variations of breath acetone that occur in ostensibly healthy individuals. Data are also presented which show that following a ketogenic diet taken by eight healthy individuals their breath acetone concentrations increased up to five times over the subsequent 6 h. Similarly, the breath acetone increased six and nine times when a low carbohydrate diet was taken by two volunteers and remained high for the several days for which the diet was continued. These new data, together with the previous data, clearly indicate that diet and natural intra-individual biological and diurnal variability result in wide variations in breath acetone concentration. This places an uncertainty in the use of breath acetone alone to monitor blood glucose and glycaemic control, except and unless the individual acts as their own control and is cognizant of the need for dietary control. (note)

  20. Making developmental biology relevant to undergraduates in an era of economic rationalism in Australia.

    Science.gov (United States)

    Key, Brian; Nurcombe, Victor

    2003-01-01

    This report describes the road map we followed at our university to accommodate three main factors: financial pressure within the university system; desire to enhance the learning experience of undergraduates; and motivation to increase the prominence of the discipline of developmental biology in our university. We engineered a novel, multi-year undergraduate developmental biology program which was "student-oriented," ensuring that students were continually exposed to the underlying principles and philosophy of this discipline throughout their undergraduate career. Among its key features are introductory lectures in core courses in the first year, which emphasize the relevance of developmental biology to tissue engineering, reproductive medicine, therapeutic approaches in medicine, agriculture and aquaculture. State-of-the-art animated computer graphics and images of high visual impact are also used. In addition, students are streamed into the developmental biology track in the second year, using courses like human embryology and courses shared with cell biology, which include practicals based on modern experimental approaches. Finally, fully dedicated third-year courses in developmental biology are undertaken in conjunction with stand-alone practical courses where students experiencefirst-hand work in a research laboratory. Our philosophy is a "cradle-to-grave" approach to the education of undergraduates so as to prepare highly motivated, enthusiastic and well-educated developmental biologists for entry into graduate programs and ultimately post-doctoral research.

  1. Single cell biology beyond the era of antibodies: relevance, challenges, and promises in biomedical research.

    Science.gov (United States)

    Abraham, Parvin; Maliekal, Tessy Thomas

    2017-04-01

    Research of the past two decades has proved the relevance of single cell biology in basic research and translational medicine. Successful detection and isolation of specific subsets is the key to understand their functional heterogeneity. Antibodies are conventionally used for this purpose, but their relevance in certain contexts is limited. In this review, we discuss some of these contexts, posing bottle neck for different fields of biology including biomedical research. With the advancement of chemistry, several methods have been introduced to overcome these problems. Even though microfluidics and microraft array are newer techniques exploited for single cell biology, fluorescence-activated cell sorting (FACS) remains the gold standard technique for isolation of cells for many biomedical applications, like stem cell therapy. Here, we present a comprehensive and comparative account of some of the probes that are useful in FACS. Further, we illustrate how these techniques could be applied in biomedical research. It is postulated that intracellular molecular markers like nucleostemin (GNL3), alkaline phosphatase (ALPL) and HIRA can be used for improving the outcome of cardiac as well as bone regeneration. Another field that could utilize intracellular markers is diagnostics, and we propose the use of specific peptide nucleic acid probes (PNPs) against certain miRNAs for cancer surgical margin prediction. The newer techniques for single cell biology, based on intracellular molecules, will immensely enhance the repertoire of possible markers for the isolation of cell types useful in biomedical research.

  2. Elements determination of clinical relevance in biological tissues Dmdmdx/J dystrophic mice strains investigated by NAA

    International Nuclear Information System (INIS)

    Metairon, Sabrina

    2012-01-01

    In this work the determination of chemistry elements in biological tissues (whole blood, bones and organs) of dystrophic mice, used as animal model of Duchenne Muscular Dystrophy (DMD), was performed using analytical nuclear technique. The aim of this work was to determine reference values of elements of clinical (Ca, Cl, K, Mg, Na) and nutritional (Br and S) relevance in whole blood, tibia, quadriceps and hearts from Dmdmdx/J (10 males and 10 females) dystrophic mice and C57BL/6J (10 males) control group mice, using Neutron Activation Analysis technique (NAA). To show in more details the alterations that this disease may cause in these biological tissues, correlations matrixes of the DMD mdx /J mouse strain were generated and compared with C57BL/6J control group. For this study 119 samples of biological tissue were irradiated in the IEA-R1 nuclear reactor at IPEN (Sao Paulo, Brazil). The concentrations of these elements in biological tissues of Dmd mdx /J and C57B/6J mice are the first indicative interval for reference values. Moreover, the alteration in some correlation coefficients data among the elements in the health status and in the diseased status indicates a connection between these elements in whole blood, tibia, quadriceps and heart. These results may help the researchers to evaluate the efficiency of new treatments and to compare the advantages of different treatment approaches before performing tests in patients with muscular dystrophy. (author)

  3. Nicotine at clinically relevant concentrations affects atrial inward rectifier potassium current sensitive to acetylcholine.

    Science.gov (United States)

    Bébarová, Markéta; Matejovič, Peter; Švecová, Olga; Kula, Roman; Šimurdová, Milena; Šimurda, Jiří

    2017-05-01

    Nicotine abuse is associated with variety of diseases including arrhythmias, most often atrial fibrillation (AF). Altered inward rectifier potassium currents including acetylcholine-sensitive current I K(Ach) are known to be related to AF pathogenesis. Since relevant data are missing, we aimed to investigate I K(Ach) changes at clinically relevant concentrations of nicotine. Experiments were performed by the whole cell patch clamp technique at 23 ± 1 °C on isolated rat atrial myocytes. Nicotine was applied at following concentrations: 4, 40 and 400 nM; ethanol at 20 mM (∼0.09%). Nicotine at 40 and 400 nM significantly activated constitutively active component of I K(Ach) with the maximum effect at 40 nM (an increase by ∼100%); similar effect was observed at -110 and -50 mV. Changes at 4 nM nicotine were negligible on average. Coapplication of 40 nM nicotine and 20 mM ethanol (which is also known to activate this current) did not show cumulative effect. In the case of acetylcholine-induced component of I K(Ach) , a dual effect of nicotine and its correlation with the current magnitude in control were apparent: the current was increased by nicotine in the cells showing small current in control and vice versa. The effect of 40 and 400 nM nicotine on acetylcholine-induced component of I K(Ach) was significantly different at -110 and -50 mV. We conclude that nicotine at clinically relevant concentrations significantly increased constitutively active component of I K(Ach) and showed a dual effect on its acetylcholine-induced component, similarly as ethanol. Synchronous application of nicotine and ethanol did not cause additive effect.

  4. Modelling low energy electron and positron tracks in biologically relevant media

    International Nuclear Information System (INIS)

    Blanco, F.; Munoz, A.; Almeida, D.; Ferreira da Silva, F.; Limao-Vieira, P.; Fuss, M.C.; Sanz, A.G.; Garcia, G.

    2013-01-01

    This colloquium describes an approach to incorporate into radiation damage models the effect of low and intermediate energy (0-100 eV) electrons and positrons, slowing down in biologically relevant materials (water and representative biomolecules). The core of the modelling procedure is a C++ computing programme named 'Low Energy Particle Track Simulation (LEPTS)', which is compatible with available general purpose Monte Carlo packages. Input parameters are carefully selected from theoretical and experimental cross section data and energy loss distribution functions. Data sources used for this purpose are reviewed showing examples of electron and positron cross section and energy loss data for interactions with different media of increasing complexity: atoms, molecules, clusters and condense matter. Finally, we show how such a model can be used to develop an effective dosimetric tool at the molecular level (i.e. nanodosimetry). Recent experimental developments to study the fragmentation induced in biologically material by charge transfer from neutrals and negative ions are also included. (authors)

  5. The asymmetric hetero-Diels-Alder reaction in the syntheses of biologically relevant compounds.

    Science.gov (United States)

    Eschenbrenner-Lux, Vincent; Kumar, Kamal; Waldmann, Herbert

    2014-10-13

    The hetero-Diels-Alder reaction is one of the most powerful transformations in the chemistry toolbox for the synthesis of aza- and oxa-heterocycles embodying multiple stereogenic centers. However, as compared to other cycloadditions, in particular the dipolar cycloadditions and the Diels-Alder reaction, the hetero-Diels-Alder reaction has been much less explored and exploited in organic synthesis. Nevertheless, this powerful transformation has opened up efficient and creative routes to biologically relevant small molecules and different natural products which contain six-membered oxygen or nitrogen ring systems. Recent developments in this field, in particular in the establishment of enantioselectively catalyzed hetero-Diels-Alder cycloadditions steered by a plethora of different catalysts and the application of the resulting small molecules in chemical biology and medicinal chemistry research, are highlighted in this Minireview. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Physical, chemical, and biological properties of radiocerium relevant to radiation protection guidelines

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    Present knowledge of the relevant physical, chemical, and biological properties of radiocerium as a basis for establishing radiation protection guidelines is summarized. The first section of the report reviews the chemical and physical properties of radiocerium relative to the biological behavior of internally-deposited cerium and other lanthanides. The second section of the report gives the sources of radiocerium in the environment and the pathways to man. The third section of the report describes the metabolic fate of cerium in several mammalian species as a basis for predicting its metabolic fate in man. The fourth section of the report considers the biomedical effects of radiocerium in light of extensive animal experimentation. The last two sections of the report describe the history of radiation protection guidelines for radiocerium and summarize data required for evaluating the adequacy of current radiation protection guidelines. Each section begins with a summary of the most important findings that follow

  7. A magnetic method to concentrate and trap biological targets

    KAUST Repository

    Li, Fuquan

    2012-11-01

    Magnetoresistive sensors in combination with magnetic particles have been used in biological applications due to, e.g., their small size and high sensitivity. A growing interest is to integrate magnetoresistive sensors with microchannels and electronics to fabricate devices that can perform complex analyses. A major task in such systems is to immobilize magnetic particles on top of the sensor surface, which is required to detect the particles\\' stray field. In the presented work, a bead concentrator, consisting of gold microstructures, at the bottom of a microchannel, is used to attract and move magnetic particles into a trap. The trap is made of a chamber with a gold microstructure underneath and is used to attract and immobilize a defined number of magnetic beads. In order to detect targets, two kinds of solutions were prepared; one containing only superparamagnetic particles, the other one containing beads with the protein Bovine serum albumin as the target and fluorescent markers. Due to the size difference between bare beads and beads with target, less magnetic beads were immobilized inside the volume chamber in case of magnetic beads with target as compared to bare magnetic beads. © 1965-2012 IEEE.

  8. [Influence of reverse osmosis concentrate on physicochemical parameters of Sini decoction material system and their relevance].

    Science.gov (United States)

    Jin, Tang-Hui; Zhang, Liu-Hong; Zhu, Hua-Xu; Guo, Li-Wei; Li, Bo; Lu, Ming-Ming

    2014-04-01

    By studying the process of reverse osmosis system for traditional Chinese medicine materials physicochemical parameters affecting the osmotic pressure of its relevance, new compound system reverse osmosis process design methods were explored. Three concentrations materials for high, middle and low were dubbed with Sini decoction as a model drug, and pretreated by 50 thousand relative molecular weight cut-off ultrafiltration membrane. The viscosity, turbidity, conductivity, salinity, TDS, pH value and osmotic pressure of each sample were determined after the reverse osmosis to study the physical and chemical parameters between their respective correlations with the osmotic pressure, and characterized by HPLC chromatograms showing changes before and after the main chemical composition of samples of reverse osmosis. Conductivity-osmotic pressure, salinity-osmotic pressure of the linear correlation coefficient, TDS-osmotic pressure between the three sets of parameters were 0.963 8, 0.932 7, 0.973 7, respectively. Reverse osmosis concentrate and its characteristic spectrum ultrafiltrate HPLC similarity were up to 0. 968 or more, except the low concentrations. There is a significant correlation between the three physicochemical parameters (conductivity, salinity, TDS) and osmotic pressure of each sample system, and there is also significant linear correlation between salinity, conductivity, TDS. The original chemical composition of Sini decoction material concentrate was completely remained after the process of reverse osmosis.

  9. Determination of the relevant market as a criterion of assessment of concentration effects in the practice of antitrust authorities

    Directory of Open Access Journals (Sweden)

    Daria Kostecka-Jurczyk

    2012-12-01

    Full Text Available Determining the relevant market is the first and the most important step in antimonopoly proceedings due to the fact that the market position of an enterprise is always determined from the relevant market perspective. In respect of mergers, establishing the relevant market is essential in analysing whether the aim of the concentration is to distort and limit competition on the market. The author of the article focuses on describing methods for determining the relevant market applied by antimonopoly authorities.

  10. Direct toxic effects of aqueous extract of cigarette smoke on cardiac myocytes at clinically relevant concentrations

    International Nuclear Information System (INIS)

    Yamada, Shigeyuki; Zhang Xiuquan; Kadono, Toshie; Matsuoka, Nobuhiro; Rollins, Douglas; Badger, Troy; Rodesch, Christopher K.; Barry, William H.

    2009-01-01

    Aims: Our goal was to determine if clinically relevant concentrations of aqueous extract of cigarette smoke (CSE) have direct deleterious effects on ventricular myocytes during simulated ischemia, and to investigate the mechanisms involved. Methods: CSE was prepared with a smoking chamber. Ischemia was simulated by metabolic inhibition (MI) with cyanide (CN) and 0 glucose. Adult rabbit and mouse ventricular myocyte [Ca 2+ ] i was measured by flow cytometry using fluo-3. Mitochondrial [Ca 2+ ] was measured with confocal microscopy, and Rhod-2 fluorescence. The mitochondrial permeability transition (MPT) was detected by TMRM fluorescence and myocyte contracture. Myocyte oxidative stress was quantified by dichlorofluorescein (DCF) fluorescence with confocal microscopy. Results: CSE 0.1% increased myocyte contracture caused by MI. The nicotine concentration (HPLC) in 0.1% CSE was 15 ng/ml, similar to that in humans after smoking cigarettes. CSE 0.1% increased mitochondrial Ca 2+ uptake, and increased the susceptibility of mitochondria to the MPT. CSE 0.1% increased DCF fluorescence in isolated myocytes, and increased [Ca 2+ ] i in paced myocytes exposed to 2.0 mM CN, 0 glucose (P-MI). These effects were inhibited by the superoxide scavenger Tiron. The effect of CSE on [Ca 2+ ] i during P-MI was also prevented by ranolazine. Conclusions: CSE in clinically relevant concentrations increases myocyte [Ca 2+ ] i during simulated ischemia, and increases myocyte susceptibility to the MPT. These effects appear to be mediated at least in part by oxidative radicals in CSE, and likely contribute to the effects of cigarette smoke to increase myocardial infarct size, and to decrease angina threshold

  11. Distinguishing Biologically Relevant Hexoses by Water Adduction to the Lithium-Cationized Molecule.

    Science.gov (United States)

    Campbell, Matthew T; Chen, Dazhe; Wallbillich, Nicholas J; Glish, Gary L

    2017-10-03

    A method to distinguish the four most common biologically relevant underivatized hexoses, d-glucose, d-galactose, d-mannose, and d-fructose, using only mass spectrometry with no prior separation/derivatization step has been developed. Electrospray of a solution containing hexose and a lithium salt generates [Hexose+Li] + . The lithium-cationized hexoses adduct water in a quadrupole ion trap. The rate of this water adduction reaction can be used to distinguish the four hexoses. Additionally, for each hexose, multiple lithiation sites are possible, allowing for multiple structures of [Hexose+Li] + . Electrospray produces at least one structure that reacts with water and at least one that does not. The ratio of unreactive lithium-cationized hexose to total lithium-cationized hexose is unique for the four hexoses studied, providing a second method for distinguishing the isomers. Use of the water adduction reaction rate or the unreactive ratio provides two separate methods for confidently (p ≤ 0.02) distinguishing the most common biologically relevant hexoses using only femtomoles of hexose. Additionally, binary mixtures of glucose and fructose were studied. A calibration curve was created by measuring the reaction rate of various samples with different ratios of fructose and glucose. The calibration curve was used to accurately measure the percentage of fructose in three samples of high fructose corn syrup (<4% error).

  12. How cyclophosphamide at environmentally relevant concentration influences Daphnia magna life history and its proteome.

    Directory of Open Access Journals (Sweden)

    Małgorzata Grzesiuk

    Full Text Available The waste of commonly used medicines is known to contaminate freshwater ecosystems. Pharmaceuticals can be toxic, mutagenic, or modifying to freshwater organisms even at low concentrations if consider their permanent presence in the environment. Chemotherapeutics used to treat cancer, and in particular alkylating agents, contribute significantly to this form of pollution, the latter introducing cytotoxic and/or mutagenic lesions to the DNA and RNA of organisms which can be disruptive to their cells. The aim of the present study was to investigate the influence of the alkylating anticancer agent cyclophosphamide (CP on Daphnia magna clones. We evaluated the life history parameters and protein profiles of this crustacean following exposure to environmentally relevant CP concentration of 10 ng L-1. Even at this low concentration, the alkylating agent caused modification of the life history parameters and proteome profile of the Daphnia. These changes were clone-specific and involved growth rate, age at first reproduction, neonate number, and proteins related to cell cycle and redox state regulation. The disturbance caused by pharmaceuticals contaminating freshwater ecosystem is probably weaker and unlikely to be cytotoxic in character due to the high dilution of these substances in the water. However, our results indicate that prolonged exposure of organisms to these toxins may lead to modifications on the organismal and molecular levels with unpredictable significance for the entire ecosystem.

  13. Bumblebees are not deterred by ecologically relevant concentrations of nectar toxins.

    Science.gov (United States)

    Tiedeken, Erin Jo; Stout, Jane C; Stevenson, Philip C; Wright, Geraldine A

    2014-05-01

    Bees visit flowers to collect nectar and pollen that contain nutrients and simultaneously facilitate plant sexual reproduction. Paradoxically, nectar produced to attract pollinators often contains deterrent or toxic plant compounds associated with herbivore defence. The functional significance of these nectar toxins is not fully understood, but they may have a negative impact on pollinator behaviour and health, and, ultimately, plant pollination. This study investigates whether a generalist bumblebee, Bombus terrestris, can detect naturally occurring concentrations of nectar toxins. Using paired-choice experiments, we identified deterrence thresholds for five compounds found in the nectar of bee-pollinated plants: quinine, caffeine, nicotine, amygdalin and grayanotoxin. The deterrence threshold was determined when bumblebees significantly preferred a sucrose solution over a sucrose solution containing the compound. Bumblebees had the lowest deterrence threshold for the alkaloid quinine (0.01 mmol l(-1)); all other compounds had higher deterrence thresholds, above the natural concentration range in floral nectar. Our data, combined with previous work using honeybees, suggest that generalist bee species have poor acuity for the detection of nectar toxins. The fact that bees do not avoid nectar-relevant concentrations of these compounds likely indicates that it is difficult for them to learn to associate floral traits with the presence of toxins, thus maintaining this trait in plant populations.

  14. Comparison of the perceived relevance of oral biology reported by students and interns of a Pakistani dental college.

    Science.gov (United States)

    Farooq, I; Ali, S

    2014-11-01

    The purpose of this study was to analyse and compare the perceived relevance of oral biology with dentistry as reported by dental students and interns and to investigate the most popular teaching approach and learning resource. A questionnaire aiming to ask about the relevance of oral biology to dentistry, most popular teaching method and learning resource was utilised in this study. Study groups encompassed second-year dental students who had completed their course and dental interns. The data were obtained and analysed statistically. The overall response rate for both groups was 60%. Both groups reported high relevance of oral biology to dentistry. Perception of dental interns regarding the relevance of oral biology to dentistry was higher than that of students. Both groups identified student presentations as the most important teaching method. Amongst the most important learning resources, textbooks were considered most imperative by interns, whereas lecture handouts received the highest importance score by students. Dental students and interns considered oral biology to be relevant to dentistry, although greater relevance was reported by interns. Year-wise advancement in dental education and training improves the perception of the students about the relevance of oral biology to dentistry. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Effects of tributyltin on metamorphosis and gonadal differentiation of Xenopus laevis at environmentally relevant concentrations.

    Science.gov (United States)

    Shi, Huahong; Zhu, Pan; Guo, Suzhen

    2014-05-01

    Tributyltin (TBT), a well known endocrine disruptor, has high teratogenicity to embryos of amphibian (Xenopus tropicalis). An amphibian metamorphosis assay (AMA) and a complete AMA (CAMA) were conducted for TBT. In AMA, the body weight, the snout-to-vent length and the hind limb length of X. laevis tadpoles were decreased in tributyltin chloride (TBTCl; 12.5-200 ng/L) treatment groups after 7 days exposure. TBT greatly retarded the development of tadpoles, decreased the number of follicle and induced thyroid follicle cell hyperplasia after 19 days exposure. In CAMA, 10 and 100 ng/L TBTCl led to various malformations of gonad, including intersex, segmental aplasia and multiple ovary cavities of X. laevis following exposure from stages 46 to stage 66. The sex ratio was male-biased in TBT treatment groups. These results suggest that TBT delayed the metamorphosis, inhibited the growth of tadpoles and disrupted the gonadal differentiation of X. laevis at environmentally relevant concentrations.

  16. Effects of tributyltin (TBT) on Xenopus tropicalis embryos at environmentally relevant concentrations.

    Science.gov (United States)

    Guo, Suzhen; Qian, Lijuan; Shi, Huahong; Barry, Terence; Cao, Qinzhen; Liu, Junqi

    2010-04-01

    Tributyltin (TBT) has been widely used as a biocide in antifouling paints and is a known endocrine disrupting chemical. In this paper, we exposed embryos of Xenopus tropicalis to 50-400ngL(-1) tributyltin chloride. TBT significantly decreased the survival rate, reduced the body length and retarded the development of embryos after 24, 36 and 48h of exposure. These effects of TBT were concentration- and time-dependent. Embryos treated with TBT showed multiple malformations. The most obvious alterations were abnormal eyes, enlarged proctodaeum, narrow fins, and skin hypopigmentation. Enlarged proctodaeum and narrow fins were mainly observed after 36 and 48h of exposure. The loss of eye pigmentation or the absence of external eyes occurred after 24 and 36h of exposure, while extended lenses or edemas of eyes were more commonly observed after 48h of exposure. Additional malformations included: small anterior region of heads, pericardial edemas, enlarged trunks, and bent tails. These results suggested that TBT is very toxic to X. tropicalis embryos at environmentally relevant concentrations.

  17. Detection of Adriamycin-DNA adducts by accelerator mass spectrometry at clinically relevant Adriamycin concentrations.

    Science.gov (United States)

    Coldwell, Kate E; Cutts, Suzanne M; Ognibene, Ted J; Henderson, Paul T; Phillips, Don R

    2008-09-01

    Limited sensitivity of existing assays has prevented investigation of whether Adriamycin-DNA adducts are involved in the anti-tumour potential of Adriamycin. Previous detection has achieved a sensitivity of a few Adriamycin-DNA adducts/10(4) bp DNA, but has required the use of supra-clinical drug concentrations. This work sought to measure Adriamycin-DNA adducts at sub-micromolar doses using accelerator mass spectrometry (AMS), a technique with origins in geochemistry for radiocarbon dating. We have used conditions previously validated (by less sensitive decay counting) to extract [(14)C]Adriamycin-DNA adducts from cells and adapted the methodology to AMS detection. Here we show the first direct evidence of Adriamycin-DNA adducts at clinically-relevant Adriamycin concentrations. [(14)C]Adriamycin treatment (25 nM) resulted in 4.4 +/- 1.0 adducts/10(7) bp ( approximately 1300 adducts/cell) in MCF-7 breast cancer cells, representing the best sensitivity and precision reported to date for the covalent binding of Adriamycin to DNA. The exceedingly sensitive nature of AMS has enabled over three orders of magnitude increased sensitivity of Adriamycin-DNA adduct detection and revealed adduct formation within an hour of drug treatment. This method has been shown to be highly reproducible for the measurement of Adriamycin-DNA adducts in tumour cells in culture and can now be applied to the detection of these adducts in human tissues.

  18. Perspectives on the relevance of the circadian time structure to workplace threshold limit values and employee biological monitoring.

    Science.gov (United States)

    Smolensky, Michael H; Reinberg, Alain E; Sackett-Lundeen, Linda

    2017-01-01

    The circadian time structure (CTS) and its disruption by rotating and nightshift schedules relative to work performance, accident risk, and health/wellbeing have long been areas of occupational medicine research. Yet, there has been little exploration of the relevance of the CTS to setting short-term, time-weighted, and ceiling threshold limit values (TLVs); conducting employee biological monitoring (BM); and establishing normative reference biological exposure indices (BEIs). Numerous publications during the past six decades document the CTS substantially affects the disposition - absorption, distribution, metabolism, and elimination - and effects of medications. Additionally, laboratory animal and human studies verify the tolerance to chemical, biological (contagious), and physical agents can differ extensively according to the circadian time of exposure. Because of slow and usually incomplete CTS adjustment by rotating and permanent nightshift workers, occupational chemical and other contaminant encounters occur during a different circadian stage than for dayshift workers. Thus, the intended protection of some TLVs when working the nightshift compared to dayshift might be insufficient, especially in high-risk settings. The CTS is germane to employee BM in that large-amplitude predictable-in-time 24h variation can occur in the concentration of urine, blood, and saliva of monitored chemical contaminants and their metabolites plus biomarkers indicative of adverse xenobiotic exposure. The concept of biological time-qualified (for rhythms) reference values, currently of interest to clinical laboratory pathology practice, is seemingly applicable to industrial medicine as circadian time and workshift-specific BEIs to improve surveillance of night workers, in particular. Furthermore, BM as serial assessments performed frequently both during and off work, exemplified by employee self-measurement of lung function using a small portable peak expiratory flow meter, can

  19. Radioactive concentrations in foodstuffs and the ingestion dose from Romanian relevant diets

    International Nuclear Information System (INIS)

    Ferdes, O.

    1994-01-01

    Radioactivity measurements of fresh fruits and vegetables, grains (wheat and bread), milk (cheese), meat and meat products from different areas have been done. High-resolution low-level gamma-ray spectrometry, low-level beta total analysis and radiochemical techniques were used. Many radionuclides, both man-made and natural, have been identified. Only a few of them (the man-made Cs, I and Sr as well as the natural 40 K, 7 Be, etc) were of biological importance. In order to predict the ingestion dose, it had to be studied the general pathway of radionuclides to man, including a transfer model to agricultural products and the processes involved in food chain contamination. Modelling the radionuclide behaviour included retention, radioactive decay, metabolic processes and retention after processing. Relevant aspects related to translocation, agricultural practices and food processing were also considered. The human dose due to radioactive intake could be assessed on the basis of a simplified model for radionuclide ingestion and assimilation, considering local conditions and specific diets. As a result the average diets were determined depending on geographical areas (urban, rural, plain and uphill) and age (children, youngsters and adults). The estimated values for yearly ingestion dose vary from a few mSv to tens of mSv (as in the case of 1986 and 1987). (author)

  20. Effect of ethanol at clinically relevant concentrations on atrial inward rectifier potassium current sensitive to acetylcholine.

    Science.gov (United States)

    Bébarová, Markéta; Matejovič, Peter; Pásek, Michal; Hořáková, Zuzana; Hošek, Jan; Šimurdová, Milena; Šimurda, Jiří

    2016-10-01

    Alcohol intoxication tends to induce arrhythmias, most often the atrial fibrillation. To elucidate arrhythmogenic mechanisms related to alcohol consumption, the effect of ethanol on main components of the ionic membrane current is investigated step by step. Considering limited knowledge, we aimed to examine the effect of clinically relevant concentrations of ethanol (0.8-80 mM) on acetylcholine-sensitive inward rectifier potassium current I K(Ach). Experiments were performed by the whole-cell patch clamp technique at 23 ± 1 °C on isolated rat and guinea-pig atrial myocytes, and on expressed human Kir3.1/3.4 channels. Ethanol induced changes of I K(Ach) in the whole range of concentrations applied; the effect was not voltage dependent. The constitutively active component of I K(Ach) was significantly increased by ethanol with the maximum effect (an increase by ∼100 %) between 8 and 20 mM. The changes were comparable in rat and guinea-pig atrial myocytes and also in expressed human Kir3.1/3.4 channels (i.e., structural correlate of I K(Ach)). In the case of the acetylcholine-induced component of I K(Ach), a dual ethanol effect was apparent with a striking heterogeneity of changes in individual cells. The effect correlated with the current magnitude in control: the current was increased by eth-anol in the cells showing small current in control and vice versa. The average effect peaked at 20 mM ethanol (an increase of the current by ∼20 %). Observed changes of action potential duration agreed well with the voltage clamp data. Ethanol significantly affected both components of I K(Ach) even in concentrations corresponding to light alcohol consumption.

  1. A magnetic method to concentrate and trap biological targets

    KAUST Repository

    Li, Fuquan; Kosel, Jü rgen

    2012-01-01

    Magnetoresistive sensors in combination with magnetic particles have been used in biological applications due to, e.g., their small size and high sensitivity. A growing interest is to integrate magnetoresistive sensors with microchannels

  2. Alkali Metal Ion Complexes with Phosphates, Nucleotides, Amino Acids, and Related Ligands of Biological Relevance. Their Properties in Solution.

    Science.gov (United States)

    Crea, Francesco; De Stefano, Concetta; Foti, Claudia; Lando, Gabriele; Milea, Demetrio; Sammartano, Silvio

    2016-01-01

    Alkali metal ions play very important roles in all biological systems, some of them are essential for life. Their concentration depends on several physiological factors and is very variable. For example, sodium concentrations in human fluids vary from quite low (e.g., 8.2 mmol dm(-3) in mature maternal milk) to high values (0.14 mol dm(-3) in blood plasma). While many data on the concentration of Na(+) and K(+) in various fluids are available, the information on other alkali metal cations is scarce. Since many vital functions depend on the network of interactions occurring in various biofluids, this chapter reviews their complex formation with phosphates, nucleotides, amino acids, and related ligands of biological relevance. Literature data on this topic are quite rare if compared to other cations. Generally, the stability of alkali metal ion complexes of organic and inorganic ligands is rather low (usually log K  Na(+) > K(+) > Rb(+) > Cs(+). For example, for citrate it is: log K ML = 0.88, 0.80, 0.48, 0.38, and 0.13 at 25 °C and infinite dilution. Some considerations are made on the main aspects related to the difficulties in the determination of weak complexes. The importance of the alkali metal ion complexes was also studied in the light of modelling natural fluids and in the use of these cations as probes for different processes. Some empirical relationships are proposed for the dependence of the stability constants of Na(+) complexes on the ligand charge, as well as for correlations among log K values of NaL, KL or LiL species (L = generic ligand).

  3. 'Fish matters': the relevance of fish skin biology to investigative dermatology.

    Science.gov (United States)

    Rakers, Sebastian; Gebert, Marina; Uppalapati, Sai; Meyer, Wilfried; Maderson, Paul; Sell, Anne F; Kruse, Charli; Paus, Ralf

    2010-04-01

    Fish skin is a multi-purpose tissue that serves numerous vital functions including chemical and physical protection, sensory activity, behavioural purposes or hormone metabolism. Further, it is an important first-line defense system against pathogens, as fish are continuously exposed to multiple microbial challenges in their aquatic habitat. Fish skin excels in highly developed antimicrobial features, many of which have been preserved throughout evolution, and infection defense principles employed by piscine skin are still operative in human skin. This review argues that it is both rewarding and important for investigative dermatologists to revive their interest in fish skin biology, as it provides insights into numerous fundamental issues that are of major relevance to mammalian skin. The basic molecular insights provided by zebrafish in vivo-genomics for genetic, regeneration and melanoma research, the complex antimicrobial defense systems of fish skin and the molecular controls of melanocyte stem cells are just some of the fascinating examples that illustrate the multiple potential uses of fish skin models in investigative dermatology. We synthesize the essentials of fish skin biology and highlight selected aspects that are of particular comparative interest to basic and clinically applied human skin research.

  4. 6,7-dimethoxy-coumarin as a probe of hydration dynamics in biologically relevant systems

    Science.gov (United States)

    Ghose, Avisek; Amaro, Mariana; Kovaricek, Petr; Hof, Martin; Sykora, Jan

    2018-04-01

    Coumarin derivatives are well known fluorescence reporters for investigating biological systems due to their strong micro-environment sensitivity. Despite having wide range of environment sensitive fluorescence probes, the potential of 6,7-dimethoxy-coumarin has not been studied extensively so far. With a perspective of its use in protein studies, namely using the unnatural amino acid technology or as a substrate for hydrolase enzymes, we study acetyloxymethyl-6,7-dimethoxycoumarin (Ac-DMC). We investigate the photophysics and hydration dynamics of this dye in aerosol-OT (AOT) reverse micelles at various water contents using the time dependent fluorescence shift (TDFS) method. The TDFS response in AOT reverse micelles from water/surfactant ratio of 0 to 20 confirms its sensitivity towards the hydration and mobility of its microenvironment. Moreover, we show that the fluorophore can be efficiently quenched by halide ions. Hence, we conclude that the 6,7-dimethoxy-methylcoumarin fluorophore is useful for studying hydration parameters in biologically relevant systems.

  5. The clinical implications and biologic relevance of neurofilament expression in gastroenteropancreatic neuroendocrine neoplasms.

    Science.gov (United States)

    Schimmack, Simon; Lawrence, Ben; Svejda, Bernhard; Alaimo, Daniele; Schmitz-Winnenthal, Hubertus; Fischer, Lars; Büchler, Markus W; Kidd, Mark; Modlin, Irvin

    2012-05-15

    Although gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) exhibit widely divergent behavior, limited biologic information (apart from Ki-67) is available to characterize malignancy. Therefore, the identification of alternative biomarkers is a key unmet need. Given the role of internexin alpha (INA) in neuronal development, the authors assessed its function in neuroendocrine cell systems and the clinical implications of its expression as a GEP-NEN biomarker. Functional assays were undertaken to investigate the mechanistic role of INA in the pancreatic BON cell line. Expression levels of INA were investigated in 50 pancreatic NENs (43 primaries, 7 metastases), 43 small intestinal NENs (25 primaries, 18 metastases), normal pancreas (n = 10), small intestinal mucosa (n = 16), normal enterochromaffin (EC) cells (n = 9), mouse xenografts (n = 4) and NEN cell lines (n = 6) using quantitative polymerase chain reaction, Western blot, and immunostaining analyses. In BON cells, decreased levels of INA messenger RNA and protein were associated with the inhibition of both proliferation and mitogen-activated protein kinase (MAPK) signaling. INA was not expressed in normal neuroendocrine cells but was overexpressed (from 2-fold to 42-fold) in NEN cell lines and murine xenografts. In pancreatic NENs, INA was overexpressed compared with pancreatic adenocarcinomas and normal pancreas (27-fold [P = .0001], and 9-fold [P = .02], respectively). INA transcripts were correlated positively with Ki-67 (correlation coefficient [r] = 0.5; P biologic information relevant to delineation of both pancreatic NEN tumor phenotypes and clinical behavior. Copyright © 2011 American Cancer Society.

  6. A biologically relevant method for considering patterns of oceanic retention in the Southern Ocean

    Science.gov (United States)

    Mori, Mao; Corney, Stuart P.; Melbourne-Thomas, Jessica; Klocker, Andreas; Sumner, Michael; Constable, Andrew

    2017-12-01

    Many marine species have planktonic forms - either during a larval stage or throughout their lifecycle - that move passively or are strongly influenced by ocean currents. Understanding these patterns of movement is important for informing marine ecosystem management and for understanding ecological processes generally. Retention of biological particles in a particular area due to ocean currents has received less attention than transport pathways, particularly for the Southern Ocean. We present a method for modelling retention time, based on the half-life for particles in a particular region, that is relevant for biological processes. This method uses geostrophic velocities at the ocean surface, derived from 23 years of satellite altimetry data (1993-2016), to simulate the advection of passive particles during the Southern Hemisphere summer season (from December to March). We assess spatial patterns in the retention time of passive particles and evaluate the processes affecting these patterns for the Indian sector of the Southern Ocean. Our results indicate that the distribution of retention time is related to bathymetric features and the resulting ocean dynamics. Our analysis also reveals a moderate level of consistency between spatial patterns of retention time and observations of Antarctic krill (Euphausia superba) distribution.

  7. Contextual Hub Analysis Tool (CHAT): A Cytoscape app for identifying contextually relevant hubs in biological networks.

    Science.gov (United States)

    Muetze, Tanja; Goenawan, Ivan H; Wiencko, Heather L; Bernal-Llinares, Manuel; Bryan, Kenneth; Lynn, David J

    2016-01-01

    Highly connected nodes (hubs) in biological networks are topologically important to the structure of the network and have also been shown to be preferentially associated with a range of phenotypes of interest. The relative importance of a hub node, however, can change depending on the biological context. Here, we report a Cytoscape app, the Contextual Hub Analysis Tool (CHAT), which enables users to easily construct and visualize a network of interactions from a gene or protein list of interest, integrate contextual information, such as gene expression or mass spectrometry data, and identify hub nodes that are more highly connected to contextual nodes (e.g. genes or proteins that are differentially expressed) than expected by chance. In a case study, we use CHAT to construct a network of genes that are differentially expressed in Dengue fever, a viral infection. CHAT was used to identify and compare contextual and degree-based hubs in this network. The top 20 degree-based hubs were enriched in pathways related to the cell cycle and cancer, which is likely due to the fact that proteins involved in these processes tend to be highly connected in general. In comparison, the top 20 contextual hubs were enriched in pathways commonly observed in a viral infection including pathways related to the immune response to viral infection. This analysis shows that such contextual hubs are considerably more biologically relevant than degree-based hubs and that analyses which rely on the identification of hubs solely based on their connectivity may be biased towards nodes that are highly connected in general rather than in the specific context of interest. CHAT is available for Cytoscape 3.0+ and can be installed via the Cytoscape App Store ( http://apps.cytoscape.org/apps/chat).

  8. Data to support "Boosted Regression Tree Models to Explain Watershed Nutrient Concentrations & Biological Condition"

    Data.gov (United States)

    U.S. Environmental Protection Agency — Spreadsheets are included here to support the manuscript "Boosted Regression Tree Models to Explain Watershed Nutrient Concentrations and Biological Condition". This...

  9. Environmentally relevant concentrations of citalopram partially inhibit feeding in the three-spine stickleback (Gasterosteus aculeatus).

    Science.gov (United States)

    Kellner, M; Porseryd, T; Porsch-Hällström, I; Hansen, S H; Olsén, K H

    2015-01-01

    Selective Serotonin Re-uptake Inhibitors (SSRI) are mood-altering, psychotropic drugs commonly used in the treatment of depression and other psychological illnesses. Many of them are poorly degraded in sewage treatment plants and enter the environment unaltered. In laboratory studies, they have been demonstrated to affect a wide range of behaviours in aquatic organisms. In this study we investigated the effect of a three-week exposure to 0.15 and 1.5 μg/l of the SSRI citalopram dissolved in the ambient water on the feeding behaviour in three-spine stickleback (Gasterosteus aculeatus). Feeding, measured as the number of attacks performed on a piece of frozen bloodworms during a 10-min period, was reduced by 30-40% in fish exposed to both 0.15 and 1.5 μg/l citalopram. The effects of the environmentally relevant concentration 0.15 μg/l on feeding, an important fitness characteristic, suggests that the ecological significance of environmental SSRI exposure may be pronounced. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Ketoconazole inhibits the cellular uptake of anandamide via inhibition of FAAH at pharmacologically relevant concentrations.

    Directory of Open Access Journals (Sweden)

    Emmelie Björklund

    Full Text Available The antifungal compound ketoconazole has, in addition to its ability to interfere with fungal ergosterol synthesis, effects upon other enzymes including human CYP3A4, CYP17, lipoxygenase and thromboxane synthetase. In the present study, we have investigated whether ketoconazole affects the cellular uptake and hydrolysis of the endogenous cannabinoid receptor ligand anandamide (AEA.The effects of ketoconazole upon endocannabinoid uptake were investigated using HepG2, CaCo2, PC-3 and C6 cell lines. Fatty acid amide hydrolase (FAAH activity was measured in HepG2 cell lysates and in intact C6 cells. Ketoconazole inhibited the uptake of AEA by HepG2 cells and CaCo2 cells with IC50 values of 17 and 18 µM, respectively. In contrast, it had modest effects upon AEA uptake in PC-3 cells, which have a low expression of FAAH. In cell-free HepG2 lysates, ketoconazole inhibited FAAH activity with an IC50 value (for the inhibitable component of 34 µM.The present study indicates that ketoconazole can inhibit the cellular uptake of AEA at pharmacologically relevant concentrations, primarily due to its effects upon FAAH. Ketoconazole may be useful as a template for the design of dual-action FAAH/CYP17 inhibitors as a novel strategy for the treatment of prostate cancer.

  11. Functionally relevant microorganisms to enhanced biological phosphorus removal performance at full-scale wastewater treatment plants in the United States.

    Science.gov (United States)

    Gu, April Z; Saunders, A; Neethling, J B; Stensel, H D; Blackall, L L

    2008-08-01

    The abundance and relevance ofAccumulibacter phosphatis (presumed to be polyphosphate-accumulating organisms [PAOs]), Competibacter phosphatis (presumed to be glycogen-accumulating organisms [GAOs]), and tetrad-forming organisms (TFOs) to phosphorus removal performance at six full-scale enhanced biological phosphorus removal (EBPR) wastewater treatment plants were investigated. Coexistence of various levels of candidate PAOs and GAOs were found at these facilities. Accumulibacter were found to be 5 to 20% of the total bacterial population, and Competibacter were 0 to 20% of the total bacteria population. The TFO abundance varied from nondetectable to dominant. Anaerobic phosphorus (P) release to acetate uptake ratios (P(rel)/HAc(up)) obtained from bench tests were correlated positively with the abundance ratio of Accumulibacter/(Competibacter +TFOs) and negatively with the abundance of (Competibacter +TFOs) for all plants except one, suggesting the relevance of these candidate organisms to EBPR processes. However, effluent phosphorus concentration, amount of phosphorus removed, and process stability in an EBPR system were not directly related to high PAO abundance or mutually exclusive with a high GAO fraction. The plant that had the lowest average effluent phosphorus and highest stability rating had the lowest P(rel)/HAc(up) and the most TFOs. Evaluation of full-scale EBPR performance data indicated that low effluent phosphorus concentration and high process stability are positively correlated with the influent readily biodegradable chemical oxygen demand-to-phosphorus ratio. A system-level carbon-distribution-based conceptual model is proposed for capturing the dynamic competition between PAOs and GAOs and their effect on an EBPR process, and the results from this study seem to support the model hypothesis.

  12. Altitude training causes haematological fluctuations with relevance for the Athlete Biological Passport

    DEFF Research Database (Denmark)

    Bonne, Thomas Christian; Lundby, Carsten; Lundby, Anne Kristine

    2015-01-01

    The impact of altitude training on haematological parameters and the Athlete Biological Passport (ABP) was evaluated in international-level elite athletes. One group of swimmers lived high and trained high (LHTH, n = 10) for three to four weeks at 2130 m or higher whereas a control group (n = 10......) completed a three-week training camp at sea-level. Haematological parameters were determined weekly three times before and four times after the training camps. ABP thresholds for haemoglobin concentration ([Hb]), reticulocyte percentage (RET%), OFF score and the abnormal blood profile score (ABPS) were...... calculated using the Bayesian model. After altitude training, six swimmers exceeded the 99% ABP thresholds: two swimmers exceeded the OFF score thresholds at day +7; one swimmer exceeded the OFF score threshold at day +28; one swimmer exceeded the threshold for RET% at day +14; and one swimmer surpassed...

  13. Stability of silver nanoparticles: agglomeration and oxidation in biological relevant conditions

    Science.gov (United States)

    Valenti, Laura E.; Giacomelli, Carla E.

    2017-05-01

    Silver nanoparticles (Ag-NP) are the most used nanomaterial in consumer products due to the intrinsic antimicrobial capacity of silver. However, Ag-NP may be also harmful to algae, aquatic species, mammalian cells, and higher plants because both Ag+ and nanoparticles are responsible of cell damages. The oxidative dissolution of Ag-NP would proceed to completion under oxic conditions, but the rate and extent of the dissolution depend on several factors. This work correlates the effect of the capping agent (albumin and citrate) with the stability of Ag-NP towards agglomeration in simulated body fluid (SBF) and oxidation in the presence of ROS species (H2O2). Capping provides colloidal stability only through electrostatic means, whereas albumin acts as bulky ligands giving steric and electrostatic repulsion, inhibiting the agglomeration in SBF. However, citrate capping protects Ag-NP from dissolution to a major extent than albumin does because of its reducing power. Moreover, citrate in solution minimizes the oxidation of albumin-coated Ag-NP even after long incubation times. H2O2-induced dissolution proceeds to completion with Ag-NP incubated in SBF, while incubation in citrate leads to an incomplete oxidation. In short, albumin is an excellent capping agent to minimize Ag-NP agglomeration whereas citrate provides a mild-reductive medium that prevents dissolution in biological relevant media as well as in the presence of ROS species. These results provide insight into how the surface properties and media composition affect the release of Ag+ from Ag-NP, related to the cell toxicity and relevant to the storage and lifetime of silver-containing nanomaterials.

  14. Stability of silver nanoparticles: agglomeration and oxidation in biological relevant conditions

    Energy Technology Data Exchange (ETDEWEB)

    Valenti, Laura E.; Giacomelli, Carla E., E-mail: giacomel@fcq.unc.edu.ar [Universidad Nacional de Córdoba, Ciudad Universitaria, Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET-UNC, Departamento de Fisicoquímica, Facultad de Ciencias Químicas (Argentina)

    2017-05-15

    Silver nanoparticles (Ag-NP) are the most used nanomaterial in consumer products due to the intrinsic antimicrobial capacity of silver. However, Ag-NP may be also harmful to algae, aquatic species, mammalian cells, and higher plants because both Ag{sup +} and nanoparticles are responsible of cell damages. The oxidative dissolution of Ag-NP would proceed to completion under oxic conditions, but the rate and extent of the dissolution depend on several factors. This work correlates the effect of the capping agent (albumin and citrate) with the stability of Ag-NP towards agglomeration in simulated body fluid (SBF) and oxidation in the presence of ROS species (H{sub 2}O{sub 2}). Capping provides colloidal stability only through electrostatic means, whereas albumin acts as bulky ligands giving steric and electrostatic repulsion, inhibiting the agglomeration in SBF. However, citrate capping protects Ag-NP from dissolution to a major extent than albumin does because of its reducing power. Moreover, citrate in solution minimizes the oxidation of albumin-coated Ag-NP even after long incubation times. H{sub 2}O{sub 2}-induced dissolution proceeds to completion with Ag-NP incubated in SBF, while incubation in citrate leads to an incomplete oxidation. In short, albumin is an excellent capping agent to minimize Ag-NP agglomeration whereas citrate provides a mild-reductive medium that prevents dissolution in biological relevant media as well as in the presence of ROS species. These results provide insight into how the surface properties and media composition affect the release of Ag{sup +} from Ag-NP, related to the cell toxicity and relevant to the storage and lifetime of silver-containing nanomaterials.

  15. Investigation of some biologically relevant redox reactions using electrochemical mass spectrometry interfaced by desorption electrospray ionization.

    Science.gov (United States)

    Lu, Mei; Wolff, Chloe; Cui, Weidong; Chen, Hao

    2012-04-01

    Recently we have shown that, as a versatile ionization technique, desorption electrospray ionization (DESI) can serve as a useful interface to combine electrochemistry (EC) with mass spectrometry (MS). In this study, the EC/DESI-MS method has been further applied to investigate some aqueous phase redox reactions of biological significance, including the reduction of peptide disulfide bonds and nitroaromatics as well as the oxidation of phenothiazines. It was found that knotted/enclosed disulfide bonds in the peptides apamin and endothelin could be electrochemically cleaved. Subsequent tandem MS analysis of the resulting reduced peptide ions using collision-induced dissociation (CID) and electron-capture dissociation (ECD) gave rise to extensive fragment ions, providing a fast protocol for sequencing peptides with complicated disulfide bond linkages. Flunitrazepam and clonazepam, a class of nitroaromatic drugs, are known to undergo reduction into amines which was proposed to involve nitroso and N-hydroxyl intermediates. Now in this study, these corresponding intermediate ions were successfully intercepted and their structures were confirmed by CID. This provides mass spectrometric evidence for the mechanism of the nitro to amine conversion process during nitroreduction, an important redox reaction involved in carcinogenesis. In addition, the well-known oxidation reaction of chlorpromazine was also examined. The putative transient one-electron transfer product, the chlorpromazine radical cation (m/z 318), was captured by MS, for the first time, and its structure was also verified by CID. In addition to these observations, some features of the DESI-interfaced electrochemical mass spectrometry were discussed, such as simple instrumentation and the lack of background signal. These results further demonstrate the feasibility of EC/DESI-MS for the study of the biology-relevant redox chemistry and would find applications in proteomics and drug development research.

  16. Action video game players' visual search advantage extends to biologically relevant stimuli.

    Science.gov (United States)

    Chisholm, Joseph D; Kingstone, Alan

    2015-07-01

    Research investigating the effects of action video game experience on cognition has demonstrated a host of performance improvements on a variety of basic tasks. Given the prevailing evidence that these benefits result from efficient control of attentional processes, there has been growing interest in using action video games as a general tool to enhance everyday attentional control. However, to date, there is little evidence indicating that the benefits of action video game playing scale up to complex settings with socially meaningful stimuli - one of the fundamental components of our natural environment. The present experiment compared action video game player (AVGP) and non-video game player (NVGP) performance on an oculomotor capture task that presented participants with face stimuli. In addition, the expression of a distractor face was manipulated to assess if action video game experience modulated the effect of emotion. Results indicate that AVGPs experience less oculomotor capture than NVGPs; an effect that was not influenced by the emotional content depicted by distractor faces. It is noteworthy that this AVGP advantage emerged despite participants being unaware that the investigation had to do with video game playing, and participants being equivalent in their motivation and treatment of the task as a game. The results align with the notion that action video game experience is associated with superior attentional and oculomotor control, and provides evidence that these benefits can generalize to more complex and biologically relevant stimuli. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Messina: a novel analysis tool to identify biologically relevant molecules in disease.

    Directory of Open Access Journals (Sweden)

    Mark Pinese

    Full Text Available BACKGROUND: Morphologically similar cancers display heterogeneous patterns of molecular aberrations and follow substantially different clinical courses. This diversity has become the basis for the definition of molecular phenotypes, with significant implications for therapy. Microarray or proteomic expression profiling is conventionally employed to identify disease-associated genes, however, traditional approaches for the analysis of profiling experiments may miss molecular aberrations which define biologically relevant subtypes. METHODOLOGY/PRINCIPAL FINDINGS: Here we present Messina, a method that can identify those genes that only sometimes show aberrant expression in cancer. We demonstrate with simulated data that Messina is highly sensitive and specific when used to identify genes which are aberrantly expressed in only a proportion of cancers, and compare Messina to contemporary analysis techniques. We illustrate Messina by using it to detect the aberrant expression of a gene that may play an important role in pancreatic cancer. CONCLUSIONS/SIGNIFICANCE: Messina allows the detection of genes with profiles typical of markers of molecular subtype, and complements existing methods to assist the identification of such markers. Messina is applicable to any global expression profiling data, and to allow its easy application has been packaged into a freely-available stand-alone software package.

  18. Extracellular membrane vesicles in blood products-biology and clinical relevance

    Directory of Open Access Journals (Sweden)

    Emilija Krstova Krajnc

    2016-01-01

    Full Text Available Extracellular membrane vesicles are fragments shed from plasma membranes off all cell types that are undergoing apoptosis or are being subjected to various types of stimulation or stress.  Even in the process of programmed cell death (apoptosis, cell fall apart of varying size vesicles. They expose phosphatidylserine (PS on the outer leaflet of their membrane, and bear surface membrane antigens reflecting their cellular origin. Extracellular membrane vesicles have been isolated from many types of biological fluids, including serum, cerebrospinal fluid, urine, saliva, tears and conditioned culture medium. Flow cytometry is one of the many different methodological approaches that have been used to analyze EMVs. The method attempts to characterize the EMVs cellular origin, size, population, number, and structure. EMVs are present and accumulate in blood products (erythrocytes, platelets as well as in fresh frozen plasma during storage. The aim of this review is to highlight the importance of extracellular vesicles as a cell-to-cell communication system and the role in the pathogenesis of different diseases. Special emphasis will be given to the implication of extracellular membrane vesicles in blood products and their clinical relevance. Although our understanding of the role of  EMVs in disease is far from comprehensive, they display promise as biomarkers for different diseases in the future and also as a marker of quality and safety in the quality control of blood products.

  19. High-temperature Ionization-induced Synthesis of Biologically Relevant Molecules in the Protosolar Nebula

    Science.gov (United States)

    Bekaert, David V.; Derenne, Sylvie; Tissandier, Laurent; Marrocchi, Yves; Charnoz, Sebastien; Anquetil, Christelle; Marty, Bernard

    2018-06-01

    Biologically relevant molecules (hereafter biomolecules) have been commonly observed in extraterrestrial samples, but the mechanisms accounting for their synthesis in space are not well understood. While electron-driven production of organic solids from gas mixtures reminiscent of the photosphere of the protosolar nebula (PSN; i.e., dominated by CO–N2–H2) successfully reproduced key specific features of the chondritic insoluble organic matter (e.g., elementary and isotopic signatures of chondritic noble gases), the molecular diversity of organic materials has never been investigated. Here, we report that a large range of biomolecules detected in meteorites and comets can be synthesized under conditions typical of the irradiated gas phase of the PSN at temperatures = 800 K. Our results suggest that organic materials—including biomolecules—produced within the photosphere would have been widely dispersed in the protoplanetary disk through turbulent diffusion, providing a mechanism for the distribution of organic meteoritic precursors prior to any thermal/photoprocessing and subsequent modification by secondary parent body processes. Using a numerical model of dust transport in a turbulent disk, we propose that organic materials produced in the photosphere of the disk would likely be associated with small dust particles, which are coupled to the motion of gas within the disk and therefore preferentially lofted into the upper layers of the disk where organosynthesis occurs.

  20. Self-assembled structures and pKa value of oleic acid in systems of biological relevance.

    Science.gov (United States)

    Salentinig, Stefan; Sagalowicz, Laurent; Glatter, Otto

    2010-07-20

    In the human digestion process, triglycerides are hydrolyzed by lipases to monoglycerides and the corresponding fatty acids. Here we report the self-assembly of structures in biologically relevant, emulsified oleic acid-monoolein mixtures at various pH values and oleic acid concentrations. Small-angle X-ray scattering, cryogenic transmission electron microscopy, and dynamic light scattering were used to investigate the structures formed, and to follow their transitions while these factors were varied. The addition of oleic acid to monoolein-based cubosomes was found to increase the critical packing parameter in the system. Structural transitions from bicontinuous cubosomes through hexosomes and micellar cubosomes (Fd3m symmetry) to emulsified microemulsions occur with increasing oleic acid concentration. At sufficiently high oleic acid concentration, the internal particle structure was also found to strongly depend on the pH of the aqueous phase: transformations from emulsified microemulsion through micellar cubosomes, hexosomes, and bicontinuous cubosomes to vesicles can be observed as a function of increasing pH. The reversible transition from liquid crystals to vesicles occurs at intestinal pH values (between pH 7 and 8). The hydrodynamic radius of the particles decreases from around 120 nm for internally structured particles to around 60 nm for vesicles. All transitions with pH are reversible. Finally, the apparent pK(a) for oleic acid in monoolein could be determined from the change of structure with pH. This value is within the physiological pH range of the intestine and depends somewhat on composition.

  1. Ultrafast relaxation dynamics of a biologically relevant probe dansyl at the micellar surface.

    Science.gov (United States)

    Sarkar, Rupa; Ghosh, Manoranjan; Pal, Samir Kumar

    2005-02-01

    We report picosecond-resolved measurement of the fluorescence of a well-known biologically relevant probe, dansyl chromophore at the surface of a cationic micelle (cetyltrimethylammonium bromide, CTAB). The dansyl chromophore has environmentally sensitive fluorescence quantum yields and emission maxima, along with large Stokes shift. In order to study the solvation dynamics of the micellar environment, we measured the fluorescence of dansyl chromophore attached to the micellar surface. The fluorescence transients were observed to decay (with time constant approximately 350 ps) in the blue end and rise with similar timescale in the red end, indicative of solvation dynamics of the environment. The solvation correlation function is measured to decay with time constant 338 ps, which is much slower than that of ordinary bulk water. Time-resolved anisotropy of the dansyl chromophore shows a bi-exponential decay with time constants 413 ps (23%) and 1.3 ns (77%), which is considerably slower than that in free solvents revealing the rigidity of the dansyl-micelle complex. Time-resolved area-normalized emission spectroscopic (TRANES) analysis of the time dependent emission spectra of the dansyl chromophore in the micellar environment shows an isoemissive point at 21066 cm-1. This indicates the fluorescence of the chromophore contains emission from two kinds of excited states namely locally excited state (prior to charge transfer) and charge transfer state. The nature of the solvation dynamics in the micellar environments is therefore explored from the time-resolved anisotropy measurement coupled with the TRANES analysis of the fluorescence transients. The time scale of the solvation is important for the mechanism of molecular recognition.

  2. Altitude training causes haematological fluctuations with relevance for the Athlete Biological Passport.

    Science.gov (United States)

    Bonne, Thomas Christian; Lundby, Carsten; Lundby, Anne Kristine; Sander, Mikael; Bejder, Jacob; Nordsborg, Nikolai Baastrup

    2015-08-01

    The impact of altitude training on haematological parameters and the Athlete Biological Passport (ABP) was evaluated in international-level elite athletes. One group of swimmers lived high and trained high (LHTH, n = 10) for three to four weeks at 2130 m or higher whereas a control group (n = 10) completed a three-week training camp at sea-level. Haematological parameters were determined weekly three times before and four times after the training camps. ABP thresholds for haemoglobin concentration ([Hb]), reticulocyte percentage (RET%), OFF score and the abnormal blood profile score (ABPS) were calculated using the Bayesian model. After altitude training, six swimmers exceeded the 99% ABP thresholds: two swimmers exceeded the OFF score thresholds at day +7; one swimmer exceeded the OFF score threshold at day +28; one swimmer exceeded the threshold for RET% at day +14; and one swimmer surpassed the ABPS threshold at day +14. In the control group, no values exceeded the individual ABP reference range. In conclusion, LHTH induces haematological changes in Olympic-level elite athletes which can exceed the individually generated references in the ABP. Training at altitude should be considered a confounding factor for ABP interpretation for up to four weeks after altitude exposure but does not consistently cause abnormal values in the ABP. Copyright © 2014 John Wiley & Sons, Ltd.

  3. Study about the relevance and the disclosure of biological assets of listed companies in BM&FBOVESPA

    Directory of Open Access Journals (Sweden)

    Luciana Holtz

    2013-08-01

    Full Text Available The main objective this article is to verify that the information content of biological assets disclosed in the financial statements are relevant and, the secondary objective perform content analysis of the notes verifying the compliance of information supplied by entities with CPC 29. The study sample was composed of publicly traded stock companies listed on the BM & FBOVESPA with data for the year 2010 and 2011. The empirical tests were conducted applying relevance models, using observations of 347 active companies characterizing a study model pooled ordinary least squares – POLS, including companies that have reported biological assets into account specific .The companies that had values of biological assets posted have had analyzed explanatory notes referring to this account. The results provide empirical evidence that the information content of biological assets disclosed by companies is not relevant to the sample. In relation the content analysis of the notes was checked a partial compliance of the standard, there is a disparity in the information disclosure practices by the companies analyzed, as well as an omission of items required by the standard. Can be inferred that loss of the relevance has occurred, in part, by the poor quality of the notes, which may make it difficult for outside users in interpreting the information disclosed.

  4. Using novel descriptor accounting for ligand-receptor interactions to define and visually explore biologically relevant chemical space.

    Science.gov (United States)

    Rabal, Obdulia; Oyarzabal, Julen

    2012-05-25

    The definition and pragmatic implementation of biologically relevant chemical space is critical in addressing navigation strategies in the overlapping regions where chemistry and therapeutically relevant targets reside and, therefore, also key to performing an efficient drug discovery project. Here, we describe the development and implementation of a simple and robust method for representing biologically relevant chemical space as a general reference according to current knowledge, independently of any reference space, and analyzing chemical structures accordingly. Underlying our method is the generation of a novel descriptor (LiRIf) that converts structural information into a one-dimensional string accounting for the plausible ligand-receptor interactions as well as for topological information. Capitalizing on ligand-receptor interactions as a descriptor enables the clustering, profiling, and comparison of libraries of compounds from a chemical biology and medicinal chemistry perspective. In addition, as a case study, R-groups analysis is performed to identify the most populated ligand-receptor interactions according to different target families (GPCR, kinases, etc.), as well as to evaluate the coverage of biologically relevant chemical space by structures annotated in different databases (ChEMBL, Glida, etc.).

  5. Developmental Testing of Liquid and Gaseous/Vaporous Decontamination on Bacterial Spores and Other Biological Warfare Agents on Military Relevant Surfaces

    Science.gov (United States)

    2016-02-11

    Vaporous Decontamination on Bacterial Spores and Other Biological Warfare Agents on Military-Relevant Surfaces 5a. CONTRACT NUMBER 5b. GRANT... DECONTAMINATION ON BACTERIAL SPORES AND OTHER BIOLOGICAL WARFARE AGENTS ON MILITARY-RELEVANT SURFACES Page Paragraph 1. SCOPE...surfaces before and after decontamination . The protocol in this TOP is based on the developed test methodologies from Edgewood Chemical Biological

  6. Effects of macro nutrient concentration on biological N2 fixation by Azotobacter vinelandii ATCC 12837

    International Nuclear Information System (INIS)

    Liew Pauline Woan Ying; Nazalan Najimudin; Jong Bor Chyan; Latiffah Noordin; Khairuddin Abdul Rahim; Amir Hamzah Ahmad Ghazali

    2010-01-01

    The dynamic changes of biological N 2 fixation by Azotobacter vinelandii ATCC 12837 under the influence of various macro nutrients, specifically phosphorus (P) and potassium (K), was investigated. In this attempt, Oryza sativa L. var. MR 219 was used as the model plant. Results obtained showed changes in the biological N 2 fixation activities with different macro nutrient(s) manipulations. The research activity enables optimisation of macro nutrients concentration for optimal/ enhanced biological N 2 fixation by A. vinelandii ATCC 12837. (author)

  7. Self-Relevance Constructions of Biology Concepts: Meaning-Making and Identity-Formation

    Science.gov (United States)

    Davidson, Yonaton Sahar

    2018-01-01

    Recent research supports the benefit of students' construction of relevance through writing about the connection of content to their life. However, most such research defines relevance narrowly as utility value--perceived instrumentality of the content to the student's career goals. Furthermore, the scope of phenomenological and conceptual…

  8. Basics and principles of particle image velocimetry (PIV) for mapping biogenic and biologically relevant flows

    NARCIS (Netherlands)

    Stamhuis, Eize J.

    2006-01-01

    Particle image velocimetry (PIV) has proven to be a very useful technique in mapping animal-generated flows or flow patterns relevant to biota. Here, theoretical background is provided and experimental details of 2-dimensional digital PIV are explained for mapping flow produced by or relevant to

  9. Relevance of air conditioning for 222Radon concentration in shops of the Savona Province, Italy

    International Nuclear Information System (INIS)

    Panatto, Donatella; Ferrari, Paola; Lai, Piero; Gallelli, Giovanni

    2006-01-01

    Radon ( 222 Rn) concentration was evaluated in shops of the Savona Province, Italy, between summer 2002 and winter 2002-2003. The main characteristics of each shops were recorded through a questionnaire investigating the ventilation rate and factors related to 222 Rn precursors in the soil and the construction materials. The main variables that were related to radon concentration were the following: age of the building, level of the shop above ground, season of the year, wind exposure, active windows, and type of heating system. Shops equipped with individual air heating/conditioning systems exhibited radon concentrations that were three times higher than those of shops heated by centralized furnaces. Our data indicate that the level of pollution in the shops was of medium level, with an expected low impact on the salespersons' health. Only in wintertime, the action level of 200 Bq m -3 for the confined environment was reached in 10 shops equipped with individual air heating/conditioning systems

  10. CellBase, a comprehensive collection of RESTful web services for retrieving relevant biological information from heterogeneous sources.

    Science.gov (United States)

    Bleda, Marta; Tarraga, Joaquin; de Maria, Alejandro; Salavert, Francisco; Garcia-Alonso, Luz; Celma, Matilde; Martin, Ainoha; Dopazo, Joaquin; Medina, Ignacio

    2012-07-01

    During the past years, the advances in high-throughput technologies have produced an unprecedented growth in the number and size of repositories and databases storing relevant biological data. Today, there is more biological information than ever but, unfortunately, the current status of many of these repositories is far from being optimal. Some of the most common problems are that the information is spread out in many small databases; frequently there are different standards among repositories and some databases are no longer supported or they contain too specific and unconnected information. In addition, data size is increasingly becoming an obstacle when accessing or storing biological data. All these issues make very difficult to extract and integrate information from different sources, to analyze experiments or to access and query this information in a programmatic way. CellBase provides a solution to the growing necessity of integration by easing the access to biological data. CellBase implements a set of RESTful web services that query a centralized database containing the most relevant biological data sources. The database is hosted in our servers and is regularly updated. CellBase documentation can be found at http://docs.bioinfo.cipf.es/projects/cellbase.

  11. The Fortymile caribou herd: novel proposed management and relevant biology, 1992-1997

    Directory of Open Access Journals (Sweden)

    Rodney D. Boertje

    2000-04-01

    Full Text Available A diverse, international Fortymile Planning Team wrote a novel Fortymile caribou herd {Rangifer tarandus granti Management Plan in 1995 (Boertje & Gardner, 1996: 56-77. The primary goal of this plan is to begin restoring the Fortymile herd to its former range; >70% of the herd's former range was abandoned as herd size declined. Specific objectives call for increasing the Fortymile herd by at least 5-10% annually from 1998-2002. We describe demographics of the herd, factors limiting the herd, and condition of the herd and range during 1992-1997. These data were useful in proposing management actions for the herd and should be instrumental in future evaluations of the plan's actions. The following points summarize herd biology relevant to management proposed by the Fortymile Planning Team: 1. Herd numbers remained relatively stable during 1990-1995 (about 22 000-23 000 caribou. On 21 June 1996 we counted about 900 additional caribou in the herd, probably a result of increased pregnancy rates in 1996. On 26 June 1997 we counted about 2500 additional caribou in the herd, probably a result of recruitment of the abundant 1996 calves and excellent early survival of the 1997 calves. The Team deemed that implementing management actions during a period of natural growth would be opportune. 2. Wolf (Canis lupus and grizzly bear (Ursus arctos predation were the most important sources of mortality, despite over a decade of the most liberal regulations in the state for harvesting of wolves and grizzly bears. Wolves were the most important predator. Wolves killed between 2000 and 3000 caribou calves annually during this study and between 1000 and 2300 older caribou; 1200-1900 calves were killed from May through September. No significant differences in annual wolf predation rates on calves or adults were observed between 1994 and early winter 1997. Reducing wolf predation was judged by the Team to be the most manageable way to help hasten or stimulate

  12. Enhanced surface functionality via plasma modification and plasma deposition techniques to create more biologically relevant materials

    Science.gov (United States)

    Shearer, Jeffrey C.

    Functionalizing nanoparticles and other unusually shaped substrates to create more biologically relevant materials has become central to a wide range of research programs. One of the primary challenges in this field is creating highly functionalized surfaces without modifying the underlying bulk material. Traditional wet chemistry techniques utilize thin film depositions to functionalize nanomaterials with oxygen and nitrogen containing functional groups, such as --OH and --NHx. These functional groups can serve to create surfaces that are amenable to cell adhesion or can act as reactive groups for further attachment of larger structures, such as macromolecules or antiviral agents. Additional layers, such as SiO2, are often added between the nanomaterial and the functionalized coating to act as a barrier films, adhesion layers, and to increase overall hydrophilicity. However, some wet chemistry techniques can damage the bulk material during processing. This dissertation examines the use of plasma processing as an alternative method for producing these highly functionalized surfaces on nanoparticles and polymeric scaffolds through the use of plasma modification and plasma enhanced chemical vapor deposition techniques. Specifically, this dissertation will focus on (1) plasma deposition of SiO2 barrier films on nanoparticle substrates; (2) surface functionalization of amine and alcohol groups through (a) plasma co-polymerization and (b) plasma modification; and (3) the design and construction of plasma hardware to facilitate plasma processing of nanoparticles and polymeric scaffolds. The body of work presented herein first examines the fabrication of composite nanoparticles by plasma processing. SiOxC y and hexylamine films were coated onto TiO2 nanoparticles to demonstrate enhanced water dispersion properties. Continuous wave and pulsed allyl alcohol plasmas were used to produce highly functionalized Fe2 O3 supported nanoparticles. Specifically, film composition was

  13. EXPOSURE TO ENVIRONMENTALLY RELEVANT CONCENTRATIONS OF DIFFERENT NONYLPHENOL FORMULATIONS IN JAPANESE MEDAKA

    Science.gov (United States)

    The time course of exposure to p-nonylphenol (NP) from two different sources was compared to equivalent exposures of 17-b-estradiol (E2) and a solvent control (ethanol: EtOH). Japanese medaka were exposed for 4 days to a nominal concentration of 20 ?g/l of either NP-I (Schenectad...

  14. Model fit versus biological relevance: Evaluating photosynthesis-temperature models for three tropical seagrass species

    OpenAIRE

    Matthew P. Adams; Catherine J. Collier; Sven Uthicke; Yan X. Ow; Lucas Langlois; Katherine R. O’Brien

    2017-01-01

    When several models can describe a biological process, the equation that best fits the data is typically considered the best. However, models are most useful when they also possess biologically-meaningful parameters. In particular, model parameters should be stable, physically interpretable, and transferable to other contexts, e.g. for direct indication of system state, or usage in other model types. As an example of implementing these recommended requirements for model parameters, we evaluat...

  15. Behaviour of radionuclides in biological and non-biological processes at very low concentrations

    International Nuclear Information System (INIS)

    Sinnaeve, J.; Frissel, M.J.; Klugt, N. van der; Geijn, S.C. van de.

    1980-01-01

    Four experiments using a 'biological exchange column', i.e. a cut papyrus stem were carried out. Prior to the passage of the labelled solution containing 250 μCi 137 Cs.l -1 , and 1 μCi 134 Cs.l -1 , the exchange sites of the stem were protonated. Two treatments were carried out, the first with 10 -4 M stable caesium in the labelled solution and the second with 10 -4 M potassium. After detection of the front of activity half way up the stem, 5 cm segments of the stem were cut and counted. (Auth.)

  16. Estradiol and endocrine disrupting compounds adversely affect development of sea urchin embryos at environmentally relevant concentrations

    International Nuclear Information System (INIS)

    Roepke, Troy A.; Snyder, Mark J.; Cherr, Gary N.

    2005-01-01

    Environmental endocrine disrupting compounds (EDCs) are a wide variety of chemicals that typically exert effects, either directly or indirectly, through receptor-mediated processes, thus mimicking endogenous hormones and/or inhibiting normal hormone activities and metabolism. Little is known about the effects of EDCs on echinoderm physiology, reproduction and development. We exposed developing sea urchin embryos (Strongylocentrotus purpuratus and Lytechinus anamesus) to two known EDCs (4-octylphenol (OCT), bisphenol A (BisA)) and to natural and synthetic reproductive hormones (17β-estradiol (E 2 ), estrone (E 1 ), estriol (E 3 ), progesterone (P 4 ) and 17α-ethynylestradiol (EE 2 )). In addition, we studied two non-estrogenic EDCs, tributyltin (TBT) and o,p-DDD. Successful development to the pluteus larval stage (96 h post-fertilization) was used to define EDC concentration-response relationships. The order of compound potency based on EC 50 values for a reduction in normal development was as follows: TBT L.anamesus > OCT > TBT S. p urpuratus >> E 2 > EE 2 > DDD >> BisA > P 4 > E 1 >> E 3 . The effect of TBT was pronounced even at concentrations substantially lower than those commonly reported in heavily contaminated areas, but the response was significantly different in the two model species. Sea urchin embryos were generally more sensitive to estrogenic EDCs and TBT than most other invertebrate larvae. Stage-specific exposure experiments were conducted to determine the most sensitive developmental periods using blastula, gastrula and post-gastrula (pluteus) stages. The stage most sensitive to E 2 , OCT and TBT was the blastula stage with less overall sensitivity in the gastrula stage, regardless of concentration. Selective estrogen receptor modulators (SERMs) were added to the experiments individually and in combination with estrogenic EDCs to interfere with potential receptor-mediated actions. Tamoxifen, a partial ER agonist, alone inhibited development at

  17. Bisphenol A Induces Superfeminization in the Ramshorn Snail (Gastropoda: Prosobranchia) at Environmentally Relevant Concentrations

    Science.gov (United States)

    Oehlmann, Jörg; Schulte-Oehlmann, Ulrike; Bachmann, Jean; Oetken, Matthias; Lutz, Ilka; Kloas, Werner; Ternes, Thomas A.

    2006-01-01

    Previous investigations have shown that bisphenol A (BPA) induces a superfeminization syndrome in the freshwater snail Marisa cornuarietis at concentrations as low as 1 μg/L. Superfemales are characterized by the formation of additional female organs, enlarged accessory sex glands, gross malformations of the pallial oviduct, and a stimulation of egg and clutch production, resulting in increased female mortality. However, these studies were challenged on the basis of incomplete experimentation. Therefore, the objective of the current approach was to bridge several gaps in knowledge by conducting additional experiments. In an initial series of experiments, study results from the reproductive phase of the snails were evaluated in the sub-micrograms per liter range. Before and after the spawning season, superfemale responses were observed [NOEC (no observed effect concentration) 7.9 ng/L, EC10 (effective concentration at 10%) 13.9 ng/L], which were absent during the spawning season. A further experiment investigated the temperature dependence of BPA responses by exposing snails at two temperatures in parallel. The adverse effect of BPA was at least partially masked at 27°C (EC10 998 ng/L) when compared with 20°C (EC10 14.8 ng/L). In M. cornuarietis, BPA acts as an estrogen receptor (ER) agonist, because effects were completely antagonized by a co-exposure to tamoxifen and Faslodex. Antiandrogenic effects of BPA, such as a significant decrease in penis length at 20°C, were also observed. Competitive receptor displacement experiments indicate the presence of androgen- and estrogen-specific binding sites. The affinity for BPA of the estrogen binding sites in M. cornuarietis is higher than that of the ER in aquatic vertebrates. The results emphasize that prosobranchs are affected by BPA at lower concentrations than are other wildlife groups, and the findings also highlight the importance of exposure conditions. PMID:16818258

  18. Bisphenol A induces superfeminization in the Ramshorn snail Marisa cornuarietis (Gastropoda: Prosobranchia) at environmentally relevant concentrations

    OpenAIRE

    Oehlmann, Jörg; Schulte-Oehlmann, Ulrike; Bachmann, Jean; Oetken, Matthias; Lutz, Ilka; Kloas, Werner; Ternes, Thomas A.

    2007-01-01

    Previous investigations have shown that bisphenol A (BPA) induces a superfeminization syndrome in the freshwater snail Marisa cornuarietis at concentrations as low as 1 μg/L. Superfemales are characterized by the formation of additional female organs, enlarged accessory sex glands, gross malformations of the pallial oviduct, and a stimulation of egg and clutch production, resulting in increased female mortality. However, these studies were challenged on the basis of incomplete experiment...

  19. Transcriptional Response of the Archaeal Ammonia Oxidizer Nitrosopumilus maritimus to Low and Environmentally Relevant Ammonia Concentrations

    OpenAIRE

    Nakagawa, Tatsunori; Stahl, David A.

    2013-01-01

    The ability of chemoautotrophic ammonia-oxidizing archaea to compete for ammonia among marine microorganisms at low ambient concentrations has been in part attributed to their extremely high affinity for ammonia, but as yet there is no mechanistic understanding of supporting metabolism. We examined transcription of selected genes for anabolic functions (CO2 fixation, ammonia transport, and cell wall synthesis) and a central catabolic function (ammonia oxidation) in the thaumarchaeon Nitrosopu...

  20. Biologically effective dose distribution based on the linear quadratic model and its clinical relevance

    International Nuclear Information System (INIS)

    Lee, Steve P.; Leu, Min Y.; Smathers, James B.; McBride, William H.; Parker, Robert G.; Withers, H. Rodney

    1995-01-01

    Purpose: Radiotherapy plans based on physical dose distributions do not necessarily entirely reflect the biological effects under various fractionation schemes. Over the past decade, the linear-quadratic (LQ) model has emerged as a convenient tool to quantify biological effects for radiotherapy. In this work, we set out to construct a mechanism to display biologically oriented dose distribution based on the LQ model. Methods and Materials: A computer program that converts a physical dose distribution calculated by a commercially available treatment planning system to a biologically effective dose (BED) distribution has been developed and verified against theoretical calculations. This software accepts a user's input of biological parameters for each structure of interest (linear and quadratic dose-response and repopulation kinetic parameters), as well as treatment scheme factors (number of fractions, fractional dose, and treatment time). It then presents a two-dimensional BED display in conjunction with anatomical structures. Furthermore, to facilitate clinicians' intuitive comparison with conventional fractionation regimen, a conversion of BED to normalized isoeffective dose (NID) is also allowed. Results: Two sample cases serve to illustrate the application of our tool in clinical practice. (a) For an orthogonal wedged pair of x-ray beams treating a maxillary sinus tumor, the biological effect at the ipsilateral mandible can be quantified, thus illustrates the so-called 'double-trouble' effects very well. (b) For a typical four-field, evenly weighted prostate treatment using 10 MV x-rays, physical dosimetry predicts a comparable dose at the femoral necks between an alternate two-fields/day and four-fields/day schups. However, our BED display reveals an approximate 21% higher BED for the two-fields/day scheme. This excessive dose to the femoral necks can be eliminated if the treatment is delivered with a 3:2 (anterio-posterior/posterio-anterior (AP

  1. Teleology then and now: the question of Kant's relevance for contemporary controversies over function in biology.

    Science.gov (United States)

    Zammito, John

    2006-12-01

    'Naturalism' is the aspiration of contemporary philosophy of biology, and Kant simply cannot be refashioned into a naturalist. Instead, epistemological 'deflation' was the decisive feature of Kant's treatment of the 'biomedical' science in his day, so it is not surprising that this might attract some philosophers of science to him today. A certain sense of impasse in the contemporary 'function talk' seems to motivate renewed interest in Kant. Kant--drawing on his eighteenth-century predecessors-provided a discerning and powerful characterization of what biologists had to explain in organic form. His difference from the rest is that he opined that it was impossible to explain it. Its 'inscrutability' was intrinsic. The third Critique essentially proposed the reduction of biology to a kind of pre-scientific descriptivism, doomed never to attain authentic scientificity, to have its 'Newton of the blade of grass'. By contrast, for Locke, and a fortiori for Buffon and his followers, 'intrinsic purposiveness' was a fact of the matter about concrete biological phenomena; the features of internal self-regulation were hypotheses arising out of actual research practice. The difference comes most vividly to light once we recognize Kant's distinction of the concept of organism from the concept of life. If biology must conceptualize self-organization as actual in the world, Kant's regulative/constitutive distinction is pointless in practice and the (naturalist) philosophy of biology has urgent work to undertake for which Kant turns out not to be very helpful.

  2. Estradiol and endocrine disrupting compounds adversely affect development of sea urchin embryos at environmentally relevant concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Roepke, Troy A. [Bodega Marine Laboratory, University of California, Davis, POB 247, Bodega Bay, CA 94923 (United States); Snyder, Mark J. [Bodega Marine Laboratory, University of California, Davis, POB 247, Bodega Bay, CA 94923 (United States); Cherr, Gary N. [Bodega Marine Laboratory, University of California, Davis, POB 247, Bodega Bay, CA 94923 (United States) and Departments of Environmental Toxicology and Nutrition, One Shields Avenue, University of California, Davis, CA 95616 (United States)]. E-mail: gncherr@ucdavis.edu

    2005-01-26

    Environmental endocrine disrupting compounds (EDCs) are a wide variety of chemicals that typically exert effects, either directly or indirectly, through receptor-mediated processes, thus mimicking endogenous hormones and/or inhibiting normal hormone activities and metabolism. Little is known about the effects of EDCs on echinoderm physiology, reproduction and development. We exposed developing sea urchin embryos (Strongylocentrotus purpuratus and Lytechinus anamesus) to two known EDCs (4-octylphenol (OCT), bisphenol A (BisA)) and to natural and synthetic reproductive hormones (17{beta}-estradiol (E{sub 2}), estrone (E{sub 1}), estriol (E{sub 3}), progesterone (P{sub 4}) and 17{alpha}-ethynylestradiol (EE{sub 2})). In addition, we studied two non-estrogenic EDCs, tributyltin (TBT) and o,p-DDD. Successful development to the pluteus larval stage (96 h post-fertilization) was used to define EDC concentration-response relationships. The order of compound potency based on EC{sub 50} values for a reduction in normal development was as follows: TBT {sub L.anamesus} > OCT > TBT {sub S.{sub p}}{sub urpuratus} >> E{sub 2} > EE{sub 2} > DDD >> BisA > P{sub 4} > E{sub 1} >> E{sub 3}. The effect of TBT was pronounced even at concentrations substantially lower than those commonly reported in heavily contaminated areas, but the response was significantly different in the two model species. Sea urchin embryos were generally more sensitive to estrogenic EDCs and TBT than most other invertebrate larvae. Stage-specific exposure experiments were conducted to determine the most sensitive developmental periods using blastula, gastrula and post-gastrula (pluteus) stages. The stage most sensitive to E{sub 2}, OCT and TBT was the blastula stage with less overall sensitivity in the gastrula stage, regardless of concentration. Selective estrogen receptor modulators (SERMs) were added to the experiments individually and in combination with estrogenic EDCs to interfere with potential receptor

  3. Transcriptional Response of the Archaeal Ammonia Oxidizer Nitrosopumilus maritimus to Low and Environmentally Relevant Ammonia Concentrations

    Science.gov (United States)

    Stahl, David A.

    2013-01-01

    The ability of chemoautotrophic ammonia-oxidizing archaea to compete for ammonia among marine microorganisms at low ambient concentrations has been in part attributed to their extremely high affinity for ammonia, but as yet there is no mechanistic understanding of supporting metabolism. We examined transcription of selected genes for anabolic functions (CO2 fixation, ammonia transport, and cell wall synthesis) and a central catabolic function (ammonia oxidation) in the thaumarchaeon Nitrosopumilus maritimus SCM1 growing at two ammonia concentrations, as measured by combined ammonia and ammonium, one well above the Km for ammonia oxidation (∼500 μM) and the other well below the Km (ammonia-replete to ammonia-limiting conditions. Transcript levels for ammonia oxidation, CO2 fixation, and one of the ammonia transport genes were approximately the same at high and low ammonia availability. Transcripts for all analyzed genes decreased with time in the complete absence of ammonia, but with various rates of decay. The new steady-state mRNA levels established are presumably more reflective of the natural physiological state of ammonia-oxidizing archaea and offer a reference for interpreting message abundance patterns in the natural environment. PMID:23995944

  4. Genomics and systems biology - How relevant are the developments to veterinary pharmacology, toxicology and therapeutics?

    NARCIS (Netherlands)

    Witkamp, R.F.

    2005-01-01

    This review discusses some of the recent developments in genomics and its current and future relevance for veterinary pharmacology and toxicology. With the rapid progress made in this field several new approaches in pharmacological and toxicological research have developed and drug discovery and

  5. Effects of environmentally relevant concentrations of atrazine on gonadal development of snapping turtles (Chelydra serpentina).

    Science.gov (United States)

    de Solla, Shane R; Martin, Pamela A; Fernie, Kimberly J; Park, Brad J; Mayne, Gregory

    2006-02-01

    The herbicide atrazine has been suspected of affecting sexual development by inducing aromatase, resulting in the increased conversion of androgens to estrogens. We used snapping turtles (Chelydra serpentina), a species in which sex is dependent on the production of estrogen through aromatase activity in a temperature-dependent manner, to investigate if environmentally relevant exposures to atrazine affected gonadal development. Eggs were incubated in soil to which atrazine was applied at a typical field application rate (3.1 L/ha), 10-fold this rate (31 L/ha), and a control rate (no atrazine) for the duration of embryonic development. The incubation temperature (25 degrees C) was selected to produce only males. Although some males with testicular oocytes and females were produced in the atrazine-treated groups (3.3-3.7%) but not in the control group, no statistical differences were found among treatments. Furthermore, snapping turtle eggs collected from natural nests in a corn field were incubated at the pivotal temperature (27.5 degrees C) at which both males and females normally would be produced, and some males had oocytes in the testes (15.4%). The presence of low numbers of males with oocytes may be a natural phenomenon, and we have limited evidence to suggest that the presence of normal males with oocytes may represent a feminizing effect of atrazine. Histological examination of the thyroid gland revealed no effect on thyroid morphology.

  6. The Relevance of Biological Sciences in the 21st Century | Onyeka ...

    African Journals Online (AJOL)

    Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives ... Biological Sciences, as the name implies, is a group of sciences, rather than a ... knowledge is better assessed by the various problems of modern civilization ... in the improvement of food supply and elimination of hereditary diseases.

  7. Physical interactions among plant MADS-box transcription factors and their biological relevance

    NARCIS (Netherlands)

    Nougalli Tonaco, I.A.

    2008-01-01

    The biological interpretation of the genome starts from transcription, and many different signaling pathways are integrated at this level. Transcription factors play a central role in the transcription process, because they select the down-stream genes and determine their spatial and temporal

  8. Is 'class effect' relevant when assessing the benefit/risk profile of a biologic agent?

    NARCIS (Netherlands)

    Sterry, W.; Kerkhof, P.C.M. van de

    2012-01-01

    Psoriasis is a chronic, genetically predisposed skin disorder, characterised by thickened scaly plaques. Although no therapy is recognised as curative, therapies aimed at symptom control include biologic agents that are generally designed to block molecular activation of cellular pathways of a

  9. Environmental biodosimetry: a biologically relevant tool for ecological risk assessment and biomonitoring

    Energy Technology Data Exchange (ETDEWEB)

    Ulsh, B. E-mail: ulshb@mcmaster.ca; Hinton, T.G.; Congdon, J.D.; Dugan, L.C.; Whicker, F.W.; Bedford, J.S

    2003-07-01

    Biodosimetry, the estimation of received doses by determining the frequency of radiation-induced chromosome aberrations, is widely applied in humans acutely exposed as a result of accidents or for clinical purposes, but biodosimetric techniques have not been utilized in organisms chronically exposed to radionuclides in contaminated environments. The application of biodosimetry to environmental exposure scenarios could greatly improve the accuracy, and reduce the uncertainties, of ecological risk assessments and biomonitoring studies, because no assumptions are required regarding external exposure rates and the movement of organisms into and out of contaminated areas. Furthermore, unlike residue analyses of environmental media environmental biodosimetry provides a genetically relevant biomarker of cumulative lifetime exposure. Symmetrical chromosome translocations can impact reproductive success, and could therefore prove to be ecologically relevant as well. We describe our experience in studying aberrations in the yellow-bellied slider turtle as an example of environmental biodosimetry.

  10. Demographic history and biologically relevant genetic variation of Native Mexicans inferred from whole-genome sequencing

    OpenAIRE

    Romero-Hidalgo, Sandra; Ochoa-Leyva, Adrián; Garcíarrubio, Alejandro; Acuña-Alonzo, Victor; Antúnez-Argüelles, Erika; Balcazar-Quintero, Martha; Barquera-Lozano, Rodrigo; Carnevale, Alessandra; Cornejo-Granados, Fernanda; Fernández-López, Juan Carlos; García-Herrera, Rodrigo; García-Ortíz, Humberto; Granados-Silvestre, Ángeles; Granados, Julio; Guerrero-Romero, Fernando

    2017-01-01

    Understanding the genetic structure of Native American populations is important to clarify their diversity, demographic history, and to identify genetic factors relevant for biomedical traits. Here, we show a demographic history reconstruction from 12 Native American whole genomes belonging to six distinct ethnic groups representing the three main described genetic clusters of Mexico (Northern, Southern, and Maya). Effective population size estimates of all Native American groups remained bel...

  11. Cork stoppers as an effective sorbent for water treatment: the removal of mercury at environmentally relevant concentrations and conditions.

    Science.gov (United States)

    Lopes, Cláudia B; Oliveira, Joana R; Rocha, Luciana S; Tavares, Daniela S; Silva, Carlos M; Silva, Susana P; Hartog, Niels; Duarte, Armando C; Pereira, E

    2014-02-01

    The technical feasibility of using stopper-derived cork as an effective biosorbent towards bivalent mercury at environmentally relevant concentrations and conditions was evaluated in this study. Only 25 mg/L of cork powder was able to achieve 94 % of mercury removal for an initial mercury concentration of 500 μg/L. It was found that under the conditions tested, the efficiency of mercury removal expressed as equilibrium removal percentage does not depend on the amount of cork or its particle size, but is very sensitive to initial metal concentration, with higher removal efficiencies at higher initial concentrations. Ion exchange was identified as one of the mechanisms involved in the sorption of Hg onto cork in the absence of ionic competition. Under ionic competition, stopper-derived cork showed to be extremely effective and selective for mercury in binary mixtures, while in complex matrices like seawater, moderate inhibition of the sorption process was observed, attributed to a change in mercury speciation. The loadings achieved are similar to the majority of literature values found for other biosorbents and for other metals, suggesting that cork stoppers can be recycled as an effective biosorbent for water treatment. However, the most interesting result is that equilibrium data show a very rare behaviour, with the isotherm presenting an almost square convex shape to the concentration axis, with an infinite slope for an Hg concentration in solution around 25 μg/L.

  12. Inorganic concepts relevant to metal binding, activity, and toxicity in a biological system

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, J.D. (Warner-Lambert Co., Ann Arbor, MI (USA). Parke-Davis Pharmaceutical Research Div.); Turner, J.E.; England, M.W. (Oak Ridge National Lab., TN (USA))

    1990-01-01

    The purpose of this paper is to review selected physical and inorganic concepts and factors which might be important in assessing and/or understanding the fact and disposition of a metal system in a biological environment. Hopefully, such inquiries will ultimately permit us to understand, rationalize, and predict differences and trends in biological effects as a function of the basic nature of a metal system and, in optimal cases, serve as input to a system of guidelines for the notion of Chemical Dosimetry.'' The plan of this paper is to first review, in general terms, the basic principles of the Crystal Field Theory (CFT), a unifying theory of bonding in metal complexes. This will provide the necessary theoretical background for the subsequent discussion of selected concepts and factors. 21 refs., 7 figs., 6 tabs.

  13. Determination of mercury concentration in biological materials by neutron activation analysis

    International Nuclear Information System (INIS)

    Munoz, L.; Gras, N.; Cortes, E.; Cassorla, V.

    1983-01-01

    The objective of this work was to obtain a confident analytical method for measuring the mercury concentration in biological materials. Destructive neutron activation analysis was used for this purpose and a radiochemical separation method was studied to isolate the mercury from its main interferences: sodium and phosphorus, because these elements in biological materials are in high concentrations. The method developed was based on the copper amalgamation under controlled conditions. Yield and reproductibility studies were performed using 203 Hg as radioactive tracer. Finally, food samples of regular consumption were analyzed and the results were compared with those recommended by FAO/WHO. (Author)

  14. Cytotoxicity of Environmentally Relevant Concentrations of Aluminum in Murine Thymocytes and Lymphocytes

    Directory of Open Access Journals (Sweden)

    Jamal Kamalov

    2011-01-01

    Full Text Available The effects of low concentrations of aluminum chloride on thymocytes and lymphocytes acutely dissociated from young mice were studied using flow cytometry with a DNA-binding dye. We demonstrate a rapid and dose-dependent injury in murine thymocytes and lymphocytes resulting from exposure to aluminum, as indicated by an increase in the entry into the cell of the DNA-binding dye, propidium iodine. A 60-minute exposure to 10 μM AlCl3 caused damage of about 5% of thymocytes, while 50% were injured after 10 minutes at 20 μM. Nearly all thymocytes showed evidence of damage at 30 μM AlCl3 after only 5 minutes of incubation. In lymphocytes, injury was observed at 15 μM AlCl3 and less than 50% of cells were injured after a 60-minute exposure to 20 μM. Injury only rarely proceeded to rapid cell death and was associated with cell swelling. These results suggest that aluminum has cytotoxic effects on cells of the immune system.

  15. Enhanced Bone Formation in Segmental Defects with BMP2 in a Biologically Relevant Molecular Context

    Science.gov (United States)

    2016-10-16

    interfere with the biological activity of the BMP2, and because radioisotope detection methods are highly sensitive and remain quantitative across a large...PRINCIPAL INVESTIGATOR: Dominik R. Haudenschild CONTRACTING ORGANIZATION: University of California, Davis Davis, CA 95618 REPORT DATE : October 2016...control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE October 2016 2. REPORT TYPE Annual 3. DATES COVERED 30 Sep 2015

  16. Consistent robustness analysis (CRA) identifies biologically relevant properties of regulatory network models.

    Science.gov (United States)

    Saithong, Treenut; Painter, Kevin J; Millar, Andrew J

    2010-12-16

    A number of studies have previously demonstrated that "goodness of fit" is insufficient in reliably classifying the credibility of a biological model. Robustness and/or sensitivity analysis is commonly employed as a secondary method for evaluating the suitability of a particular model. The results of such analyses invariably depend on the particular parameter set tested, yet many parameter values for biological models are uncertain. Here, we propose a novel robustness analysis that aims to determine the "common robustness" of the model with multiple, biologically plausible parameter sets, rather than the local robustness for a particular parameter set. Our method is applied to two published models of the Arabidopsis circadian clock (the one-loop [1] and two-loop [2] models). The results reinforce current findings suggesting the greater reliability of the two-loop model and pinpoint the crucial role of TOC1 in the circadian network. Consistent Robustness Analysis can indicate both the relative plausibility of different models and also the critical components and processes controlling each model.

  17. Model fit versus biological relevance: Evaluating photosynthesis-temperature models for three tropical seagrass species.

    Science.gov (United States)

    Adams, Matthew P; Collier, Catherine J; Uthicke, Sven; Ow, Yan X; Langlois, Lucas; O'Brien, Katherine R

    2017-01-04

    When several models can describe a biological process, the equation that best fits the data is typically considered the best. However, models are most useful when they also possess biologically-meaningful parameters. In particular, model parameters should be stable, physically interpretable, and transferable to other contexts, e.g. for direct indication of system state, or usage in other model types. As an example of implementing these recommended requirements for model parameters, we evaluated twelve published empirical models for temperature-dependent tropical seagrass photosynthesis, based on two criteria: (1) goodness of fit, and (2) how easily biologically-meaningful parameters can be obtained. All models were formulated in terms of parameters characterising the thermal optimum (T opt ) for maximum photosynthetic rate (P max ). These parameters indicate the upper thermal limits of seagrass photosynthetic capacity, and hence can be used to assess the vulnerability of seagrass to temperature change. Our study exemplifies an approach to model selection which optimises the usefulness of empirical models for both modellers and ecologists alike.

  18. Model fit versus biological relevance: Evaluating photosynthesis-temperature models for three tropical seagrass species

    Science.gov (United States)

    Adams, Matthew P.; Collier, Catherine J.; Uthicke, Sven; Ow, Yan X.; Langlois, Lucas; O'Brien, Katherine R.

    2017-01-01

    When several models can describe a biological process, the equation that best fits the data is typically considered the best. However, models are most useful when they also possess biologically-meaningful parameters. In particular, model parameters should be stable, physically interpretable, and transferable to other contexts, e.g. for direct indication of system state, or usage in other model types. As an example of implementing these recommended requirements for model parameters, we evaluated twelve published empirical models for temperature-dependent tropical seagrass photosynthesis, based on two criteria: (1) goodness of fit, and (2) how easily biologically-meaningful parameters can be obtained. All models were formulated in terms of parameters characterising the thermal optimum (Topt) for maximum photosynthetic rate (Pmax). These parameters indicate the upper thermal limits of seagrass photosynthetic capacity, and hence can be used to assess the vulnerability of seagrass to temperature change. Our study exemplifies an approach to model selection which optimises the usefulness of empirical models for both modellers and ecologists alike.

  19. Solid-supported synthesis: From pharmacologically relevant heterocycles to biologically active surfaces

    DEFF Research Database (Denmark)

    Komnatnyy, Vitaly V.

    for solid-phase synthesis, methods for on - and off-bead screening of combinatorial libraries and their applic ation to various biological targets. The first part of the thesis is dedicated to the development of methodology for the synthesis of structurally diverse heterocyclic scaffolds via N...... methods for the controlled organo-functionalization of titanium, one of the most prominent materials in medicinal device industry, have been suggested . Initial acidic and oxidative treatment s of the metal surface genera te reactive hydroxyl moieties , which are subsequently modified with synthetically...... versatile amine -containing reagents. Subsequent applications in antimicrobial peptide synthesis, metal -catalysis, release from the surface, and polymer grafti ng, are also presented....

  20. Biological, clinical and population relevance of 95 loci for blood lipids

    NARCIS (Netherlands)

    T.M. Teslovich (Tanya); K. Musunuru (Kiran); A.V. Smith (Albert Vernon); A.C. Edmondson (Andrew); I.M. Stylianou (Ioannis); M. Koseki (Masahiro); J.P. Pirruccello (James); S. Ripatti (Samuli); D.I. Chasman (Daniel); C.J. Willer (Cristen); C.T. Johansen (Christopher); S.W. Fouchier (Sigrid); A.J. Isaacs (Aaron); G.M. Peloso (Gina); M. Barbalic (maja); S.L. Ricketts (Sally); J.C. Bis (Joshua); Y.S. Aulchenko (Yurii); G. Thorleifsson (Gudmar); M.F. Feitosa (Mary Furlan); J. Chambers (John); M. Orho-Melander (Marju); O. Melander (Olle); T. Johnson (Toby); X. Li (Xiaohui); X. Guo (Xiuqing); Y. Shin Cho (Yoon); M. Jin Go (Min); Y. Jin Kim (Young); J.Y. Lee (Jong Young); T. Park (Taesung); Y-J. Kim (Yong-Jin); X. Sim (Xueling); R. Twee-Hee Ong (Rick); D.C. Croteau-Chonka (Damien); L.A. Lange (Leslie); K. Song (Kijoung); J.H. Zhao (Jing Hua); X. Yuan (Xin); J. Luan; C. Lamina (Claudia); A. Ziegler (Andreas); W. Zhang (Weibo); R.Y.L. Zee (Robert); A.F. Wright (Alan); J.C.M. Witteman (Jacqueline); J.F. Wilson (James); G.A.H.M. Willemsen (Gonneke); H.E. Wichmann (Heinz Erich); J. Whitfield (John); D. Waterworth (Dawn); N.J. Wareham (Nick); G. Waeber (Gérard); P. Vollenweider (Peter); B.F. Voight (Benjamin); V. Vitart (Veronique); A.G. Uitterlinden (André); M. Uda (Manuela); J. Tuomilehto (Jaakko); J.R. Thompson (John); T. Tanaka (Toshiko); I. Surakka (Ida); H.M. Stringham (Heather); T.D. Spector (Timothy); N. Soranzo (Nicole); J.H. Smit (Johannes); J. Sinisalo (Juha); K. Silander (Kaisa); E.J.G. Sijbrands (Eric); A. Scuteri (Angelo); J. Scott (James); D. Schlessinger (David); S. Sanna (Serena); V. Salomaa (Veikko); J. Saharinen (Juha); C. Sabatti (Chiara); A. Ruokonen (Aimo); I. Rudan (Igor); L.M. Rose (Lynda); R. Roberts (Robert); M. Rieder (Mark); B.M. Psaty (Bruce); P.P. Pramstaller (Peter Paul); I. Pichler (Irene); M. Perola (Markus); B.W.J.H. Penninx (Brenda); N.L. Pedersen (Nancy); C. Pattaro (Cristian); A.N. Parker (Alex); G. Pare (Guillaume); B.A. Oostra (Ben); M.S. Nieminen (Markku); D.A. Nickerson (Deborah); G.W. Montgomery (Grant); T. Meitinger (Thomas); R. McPherson (Ruth); M.I. McCarthy (Mark); W.L. McArdle (Wendy); D. Masson (David); N.G. Martin (Nicholas); F. Marroni (Fabio); M. Mangino (Massimo); P.K. Magnusson (Patrik); G. Lucas (Gavin); R.N. Luben (Robert); R.J.F. Loos (Ruth); M.L. Lokki; G. Lettre (Guillaume); C. Langenberg (Claudia); L.J. Launer (Lenore); E. Lakatta (Edward); R. Laaksonen (Reijo); K.O. Kyvik (Kirsten Ohm); F. Kronenberg (Florian); I.R. König (Inke); K-T. Khaw (Kay-Tee); J. Kaprio (Jaakko); R.C. Kaplan (Robert); A. Johansson (Åsa); M.-R. Jarvelin (Marjo-Riitta); A. Cecile (A.); E. Ingelsson (Erik); W. Igl (Wilmar); G. Kees Hovingh; J.J. Hottenga (Jouke Jan); A. Hofman (Albert); A.A. Hicks (Andrew); C. Hengstenberg (Christian); I.M. Heid (Iris); C. Hayward (Caroline); A.S. Havulinna (Aki); N. Hastie (Nick); T.B. Harris (Tamara); T. Haritunians (Talin); A.S. Hall (Alistair); U. Gyllensten (Ulf); C. Guiducci (Candace); L. Groop (Leif); E. Gonzalez (Elena); C. Gieger (Christian); N.B. Freimer (Nelson); L. Ferrucci (Luigi); J. Erdmann (Jeanette); P. Elliott (Paul); K.G. Ejebe (Kenechi); A. Döring (Angela); A. Dominiczak (Anna); S. Demissie (Serkalem); P. Deloukas (Panagiotis); E.J.C. de Geus (Eco); U. de Faire (Ulf); G. Crawford (Gabe); F.S. Collins (Francis); C. Chen (Chao); M. Caulfield (Mark); H. Campbell (Harry); N.P. Burtt (Noël); L.L. Bonnycastle (Lori); D.I. Boomsma (Dorret); S.M. Boekholdt (Matthijs); R.N. Bergman (Richard); I.E. Barroso (Inês); S. Bandinelli (Stefania); C. Ballantyne (Christie); T.L. Assimes (Themistocles); T. Quertermous (Thomas); D. Altshuler (David); M. Seielstad (Mark); T.Y. Wong (Tien Yin); E.S. Tai (Shyong); A.B. Feranil (Alan); C.W. Kuzawa (Christopher); L.S. Adair (Linda); H.A. Taylor (Herman); I.B. Borecki (Ingrid); S.B. Gabriel (Stacey); H. Holm (Hilma); U. Thorsteinsdottir (Unnur); V. Gudnason (Vilmundur); R.M. Krauss (Ronald); K.L. Mohlke (Karen); J.M. Ordovas (Jose); P. Munroe (Patricia); J.S. Kooner (Jaspal); A.R. Tall (Alan); R.A. Hegele (Robert); J.J.P. Kastelein (John); E.E. Schadt (Eric); J.I. Rotter (Jerome); E.A. Boerwinkle (Eric); D.P. Strachan (David); V. Mooser (Vincent); J-A. Zwart (John-Anker); M.P. Reilly (Muredach); N.J. Samani (Nilesh); H. Schunkert (Heribert); L.A. Cupples (Adrienne); M.S. Sandhu (Manjinder); P.M. Ridker (Paul); D.J. Rader (Daniel); P. Tikka-Kleemola (Päivi); L. Peltonen (Leena Johanna); G.R. Abecasis (Gonçalo); M. Boehnke (Michael); S. Kathiresan (Sekar); C.J. O'Donnell (Christopher)

    2010-01-01

    textabstractPlasma concentrations of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides are among the most important risk factors for coronary artery disease (CAD) and are targets for therapeutic intervention. We screened the genome for

  1. The relevance of nanoscale biological fragments for ice nucleation in clouds

    Science.gov (United States)

    O‧Sullivan, D.; Murray, B. J.; Ross, J. F.; Whale, T. F.; Price, H. C.; Atkinson, J. D.; Umo, N. S.; Webb, M. E.

    2015-01-01

    Most studies of the role of biological entities as atmospheric ice-nucleating particles have focused on relatively rare supermicron particles such as bacterial cells, fungal spores and pollen grains. However, it is not clear that there are sufficient numbers of these particles in the atmosphere to strongly influence clouds. Here we show that the ice-nucleating activity of a fungus from the ubiquitous genus Fusarium is related to the presence of nanometre-scale particles which are far more numerous, and therefore potentially far more important for cloud glaciation than whole intact spores or hyphae. In addition, we quantify the ice-nucleating activity of nano-ice nucleating particles (nano-INPs) washed off pollen and also show that nano-INPs are present in a soil sample. Based on these results, we suggest that there is a reservoir of biological nano-INPs present in the environment which may, for example, become aerosolised in association with fertile soil dust particles.

  2. The influence of biological and environmental factors on metallothionein concentration in the blood.

    Science.gov (United States)

    Kowalska, Katarzyna; Bizoń, Anna; Zalewska, Marta; Milnerowicz, Halina

    2015-01-01

    The concentration of metallothionein (MT), a low-molecular-weight protein, is regulated by many factors, primarily metals (zinc, cadmium, copper), cytokines, glucocorticoides and free radicals. These factors are determined by such aspects of human biology as gender, pregnancy and age, as well as by environmental factors including the use of oral contraceptives and cigarette smoking, all which may affect MT levels in the body. The aim of this study was to investigate the influence of these biological and environmental factors on MT concentrations in erythrocyte lysate and in plasma. MT concentrations were determined by a two-step direct enzyme-linked immunosorbent assay. Evaluation of exposure to cigarette smoking was performed by checking cotinine levels in the plasma of subjects. The studies showed higher MT concentrations in both the erythrocyte lysate and plasma of women when compared to men. Furthermore, pregnancy causes an increase of MT concentration in plasma, while oral contraceptives cause an elevated concentration of MT in erythrocyte lysate. Age impacts plasma MT concentrations in men, whereas it does not affect concentrations of MT in erythrocyte lysate. Copyright © 2014 Elsevier GmbH. All rights reserved.

  3. Assessing therapeutic relevance of biologically interesting, ampholytic substances based on their physicochemical and spectral characteristics with chemometric tools

    Science.gov (United States)

    Judycka, U.; Jagiello, K.; Bober, L.; Błażejowski, J.; Puzyn, T.

    2018-06-01

    Chemometric tools were applied to investigate the biological behaviour of ampholytic substances in relation to their physicochemical and spectral properties. Results of the Principal Component Analysis suggest that size of molecules and their electronic and spectral characteristics are the key properties required to predict therapeutic relevance of the compounds examined. These properties were used for developing the structure-activity classification model. The classification model allows assessing the therapeutic behaviour of ampholytic substances on the basis of solely values of descriptors that can be obtained computationally. Thus, the prediction is possible without necessity of carrying out time-consuming and expensive laboratory tests, which is its main advantage.

  4. A rapid Q-PCR titration protocol for adenovirus and helper-dependent adenovirus vectors that produces biologically relevant results

    Science.gov (United States)

    Gallaher, Sean D.; Berk, Arnold J.

    2013-01-01

    Adenoviruses are employed in the study of cellular processes and as expression vectors used in gene therapy. The success and reproducibility of these studies is dependent in part on having accurate and meaningful titers of replication competent and helper-dependent adenovirus stocks, which is problematic due to the use of varied and divergent titration protocols. Physical titration methods, which quantify the total number of viral particles, are used by many, but are poor at estimating activity. Biological titration methods, such as plaque assays, are more biologically relevant, but are time consuming and not applicable to helper-dependent gene therapy vectors. To address this, a protocol was developed called “infectious genome titration” in which viral DNA is isolated from the nuclei of cells ~3 h post-infection, and then quantified by Q-PCR. This approach ensures that only biologically active virions are counted as part of the titer determination. This approach is rapid, robust, sensitive, reproducible, and applicable to all forms of adenovirus. Unlike other Q-PCR-based methods, titers determined by this protocol are well correlated with biological activity. PMID:23624118

  5. Carcinogenesis-relevant biological events in the pathophysiology of the efferocytosis phenomenon

    Directory of Open Access Journals (Sweden)

    Gargi Sachin Sarode

    2017-12-01

    Full Text Available The effective removal of cells undergoing programmed cell death, which is referred to as efferocytosis, prevents the leakage of intracellular contents into the surrounding tissue, which could lead to tissue damage and inflammation. Efferocytosis involves a coordinated orchestration of multiple steps that lead to a swift, coherent and immunologically silent removal of dying cells. The release of wound healing cytokines, which resolve inflammation and enhance tissue repair, is an important feature of efferocytosis. However, in addition to the healing cytokines released during efferocytosis, the immunosuppressive action of cytokines promotes the tumor microenvironment, enhances the motility of cancer cells and promotes the evasion of antitumor immunity. The aim of the present review was to comprehensively discuss the efferocytosis phenomenon, the important players associated with this process and their role in cancer-related biological events.

  6. Dependence of radiocaesium biological half-life in freshwater fish on water potassium concentration and temperature

    International Nuclear Information System (INIS)

    Carreiro, M.C.V.; Corisco, J.A.G.

    1998-01-01

    Short-term experiments (35-49 days) showed that the rate of cesium elimination from fish increases with increasing potassium concentration in water (the biological half-life decreases); this, however, is only true of the potassium concentration range of 0.35 to 3.5 ppm, whereas higher potassium concentrations do not seem to affect the elimination rate. Decrease in water temperature within the 20 degC to 5 degC range slows down the cesium elimination process. (P.A.)

  7. Selective uptake and biological consequences of environmentally relevant antidepressant pharmaceutical exposures on male fathead minnows

    Science.gov (United States)

    Schultz, Melissa M.; Painter, Meghan M.; Bartell, Stephen E.; Logue, Amanda; Furlong, Edward T.; Werner, Stephen L.; Schoenfuss, Heiko L.

    2011-01-01

    Antidepressant pharmaceuticals have been reported in wastewater effluent at the nanogram to low microgram-per-liter range, and include bupropion (BUP), fluoxetine (FLX), sertraline (SER), and venlafaxine (VEN). To assess the effects of antidepressants on reproductive anatomy, physiology, and behavior, adult male fathead minnows (Pimeplwles promelas) were exposed for 21 days either to a single concentration of the antidepressants FLX, SER, VEN, or BUP, or to an antidepressant mixture. The data demonstrated that exposure to VEN (305 ng/L and 1104 ng/L) and SER (5.2 ng/L) resulted in mortality. Anatomical alterations were noted within the testes of fish exposed to SER and FLX, both modulators of the neurotransmitter serotonin. Additionally, FLX at 28 ng/L induced vitellogenin in male fish—a common endpoint for estrogenic endocrine disruption. Significant alterations in male secondary sex characteristics were noted with single exposures. Effects of single compound exposures neither carried over, nor became additive in the antidepressant mixtures, and reproductive behavior was not affected. Analysis of brain tissues from the exposed fish suggested increased uptake of FLX, SER and BUP and minimal uptake of VEN when compared to exposure water concentrations. Furthermore, the only metabolite detected consistently in the brain tissues was norfluoxetine. Similar trends of uptake by brain tissue were observed when fish were exposed to antidepressant mixtures. The present study demonstrates that anatomy and physiology, but not reproductive behavior, can be disrupted by exposure to environmental concentrations of some antidepressants. The observation that antidepressant uptake into fish tissues is selective may have consequences on assessing the mode-of-action and effects of these compounds in future studies.

  8. Relevance of histamine and tryptase concentrations in nasal secretions after nasal challenges with phosphate buffered saline and allergen

    Directory of Open Access Journals (Sweden)

    D. Wang

    1995-01-01

    Full Text Available In this prospective study, a quantitative determination of histamine and tryptase in nasal secretions after nasal phosphate buffered saline (PBS and allergen challenge was performed in 18 atopic patients who were compared with ten non-allergic healthy volunteers. The aim of the study was to determine the normal and pathological concentrations of these important mediators in nasal secretions. The second objective was to test the relevance of these two mast cell secreted mediators after nasal challenge. Results showed that the concentrations of tryptase in almost all samples were under the minimal detection limit (< 0.5 μU/g and only a sigrtificant increase of tryptase (median, 28 μU/g occurred immediately after nasal allergen challenge in the patient group. Histamine concentration significantly increased after every nasal PBS challenge (median, 69 ng/g after first PBS challenge and 165 ng/g after second PBS challenge in the control group, as well as in the patient group after both PBS (median, 69 ng/g and allergen (median, 214 ng/g challenge. On the other hand, a rapid onset of sneezing and increase in nasal airway resistance was experienced only in the patient group after nasal allergen challenge, but did not occur after PBS challenge even though the histamine concentrations significantly increased in both groups. This study suggests that tryptase is a more preferable marker than histamine in quantitative monitoring of mast cell activation especially during the early phase nasal allergic reaction.

  9. Handheld Device Adapted to Smartphone Cameras for the Measurement of Sodium Ion Concentrations at Saliva-Relevant Levels via Fluorescence

    Directory of Open Access Journals (Sweden)

    Michelle Lipowicz

    2015-06-01

    Full Text Available The use of saliva sampling as a minimally-invasive means for drug testing and monitoring physiology is a subject of great interest to researchers and clinicians. This study describes a new optical method based on non-axially symmetric focusing of light using an oblate spheroid sample chamber. The device is simple, lightweight, low cost and is easily attached to several different brands/models of smartphones (Apple, Samsung, HTC and Nokia for the measurement of sodium ion levels at physiologically-relevant saliva concentrations. The sample and fluorescent reagent solutions are placed in a specially-designed, lightweight device that excludes ambient light and concentrates 470-nm excitation light, from a low-power photodiode, within the sample through non-axially-symmetric refraction. The study found that smartphone cameras and post-image processing quantitated sodium ion concentration in water over the range of 0.5–10 mM, yielding best-fit regressions of the data that agree well with a data regression of microplate luminometer results. The data suggest that fluorescence can be used for the measurement of salivary sodium ion concentrations in low-resource or point-of-care settings. With further fluorescent assay testing, the device may find application in a variety of enzymatic or chemical assays.

  10. Biological Production of a Hydrocarbon Fuel Intermediate Polyhydroxybutyrate (Phb) from a Process Relevant Lignocellulosic Derived Sugar

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei; Mohagheghi, Ali; Mittal, Ashutosh; Pilath, Heidi; Johnson, David K.

    2015-03-22

    PHAs are synthesized by many microorganisms to serve as intracellular carbon storage molecules. In some bacterial strains, PHB can account for up to 80% of cell mass. In addition to its application in the packaging sector, PHB also has great potential as an intermediate in the production of hydrocarbon fuels. PHB can be thermally depolymerized and decarboxylated to propene which can be upgraded to hydrocarbon fuels via commercial oligomerization technologies. In recent years a great effort has been made in bacterial production of PHB, yet the production cost of the polymer is still much higher than conventional petrochemical plastics. The high cost of PHB is because the cost of the substrates can account for as much as half of the total product cost in large scale fermentation. Thus searching for cheaper and better substrates is very necessary for PHB production. In this study, we demonstrate production of PHB by Cupriavidus necator from a process relevant lignocellulosic derived sugar stream, i.e., saccharified hydrolysate slurry from pretreated corn stover. Good cell growth was observed on slurry saccharified with advanced enzymes and 40~60% of PHB was accumulated in the cells. The mechanism of inhibition in the toxic hydrolysate generated by pretreatment and saccharification of biomass, will be discussed.

  11. Optimization of free ammonia concentration for nitrite accumulation in shortcut biological nitrogen removal process.

    Science.gov (United States)

    Chung, Jinwook; Shim, Hojae; Park, Seong-Jun; Kim, Seung-Jin; Bae, Wookeun

    2006-03-01

    A shortcut biological nitrogen removal (SBNR) utilizes the concept of a direct conversion of ammonium to nitrite and then to nitrogen gas. A successful SBNR requires accumulation of nitrite in the system and inhibition of the activity of nitrite oxidizers. A high concentration of free ammonia (FA) inhibits nitrite oxidizers, but unfortunately decreases the ammonium removal rate as well. Therefore, the optimal range of FA concentration is necessary not only to stabilize nitrite accumulation but also to achieve maximum ammonium removal. In order to derive such optimal FA concentrations, the specific substrate utilization rates of ammonium and nitrite oxidizers were measured. The optimal FA concentration range appeared to be 5-10 mg/L for the adapted sludge. The simulated results from the modified inhibition model expressed by FA and ammonium/nitrite concentrations were shown very similar to the experimental results.

  12. X-ray microanalytical surveys of minor element concentrations in unsectioned biological samples

    Science.gov (United States)

    Schofield, R. M. S.; Lefevre, H. W.; Overley, J. C.; Macdonald, J. D.

    1988-03-01

    Approximate concentration maps of small unsectioned biological samples are made using the pixel by pixel ratio of PIXE images to areal density images. Areal density images are derived from scanning transmission ion microscopy (STIM) proton energy-loss images. Corrections for X-ray production cross section variations, X-ray attenuation, and depth averaging are approximated or ignored. Estimates of the magnitude of the resulting error are made. Approximate calcium concentrations within the head of a fruit fly are reported. Concentrations in the retinula cell region of the eye average about 1 mg/g dry weight. Concentrations of zinc in the mandible of several ant species average about 40 mg/g. Zinc concentrations in the stomachs of these ants are at least 1 mg/g.

  13. G Quadruplex in Plants: A Ubiquitous Regulatory Element and Its Biological Relevance.

    Science.gov (United States)

    Yadav, Vikas; Hemansi; Kim, Nayun; Tuteja, Narendra; Yadav, Puja

    2017-01-01

    G quadruplexes (G4) are higher-order DNA and RNA secondary structures formed by G-rich sequences that are built around tetrads of hydrogen-bonded guanine bases. Potential G4 quadruplex sequences have been identified in G-rich eukaryotic non-telomeric and telomeric genomic regions. Upon function, G4 formation is known to involve in chromatin remodeling, gene regulation and has been associated with genomic instability, genetic diseases and cancer progression. The natural role and biological validation of G4 structures is starting to be explored, and is of particular interest for the therapeutic interventions for human diseases. However, the existence and physiological role of G4 DNA and G4 RNA in plants species have not been much investigated yet and therefore, is of great interest for the development of improved crop varieties for sustainable agriculture. In this context, several recent studies suggests that these highly diverse G4 structures in plants can be employed to regulate expression of genes involved in several pathophysiological conditions including stress response to biotic and abiotic stresses as well as DNA damage. In the current review, we summarize the recent findings regarding the emerging functional significance of G4 structures in plants and discuss their potential value in the development of improved crop varieties.

  14. G Quadruplex in Plants: A Ubiquitous Regulatory Element and Its Biological Relevance

    Directory of Open Access Journals (Sweden)

    Vikas Yadav

    2017-07-01

    Full Text Available G quadruplexes (G4 are higher-order DNA and RNA secondary structures formed by G-rich sequences that are built around tetrads of hydrogen-bonded guanine bases. Potential G4 quadruplex sequences have been identified in G-rich eukaryotic non-telomeric and telomeric genomic regions. Upon function, G4 formation is known to involve in chromatin remodeling, gene regulation and has been associated with genomic instability, genetic diseases and cancer progression. The natural role and biological validation of G4 structures is starting to be explored, and is of particular interest for the therapeutic interventions for human diseases. However, the existence and physiological role of G4 DNA and G4 RNA in plants species have not been much investigated yet and therefore, is of great interest for the development of improved crop varieties for sustainable agriculture. In this context, several recent studies suggests that these highly diverse G4 structures in plants can be employed to regulate expression of genes involved in several pathophysiological conditions including stress response to biotic and abiotic stresses as well as DNA damage. In the current review, we summarize the recent findings regarding the emerging functional significance of G4 structures in plants and discuss their potential value in the development of improved crop varieties.

  15. TaBoo SeArch Algorithm with a Modified Inverse Histogram for Reproducing Biologically Relevant Rare Events of Proteins.

    Science.gov (United States)

    Harada, Ryuhei; Takano, Yu; Shigeta, Yasuteru

    2016-05-10

    The TaBoo SeArch (TBSA) algorithm [ Harada et al. J. Comput. Chem. 2015 , 36 , 763 - 772 and Harada et al. Chem. Phys. Lett. 2015 , 630 , 68 - 75 ] was recently proposed as an enhanced conformational sampling method for reproducing biologically relevant rare events of a given protein. In TBSA, an inverse histogram of the original distribution, mapped onto a set of reaction coordinates, is constructed from trajectories obtained by multiple short-time molecular dynamics (MD) simulations. Rarely occurring states of a given protein are statistically selected as new initial states based on the inverse histogram, and resampling is performed by restarting the MD simulations from the new initial states to promote the conformational transition. In this process, the definition of the inverse histogram, which characterizes the rarely occurring states, is crucial for the efficiency of TBSA. In this study, we propose a simple modification of the inverse histogram to further accelerate the convergence of TBSA. As demonstrations of the modified TBSA, we applied it to (a) hydrogen bonding rearrangements of Met-enkephalin, (b) large-amplitude domain motions of Glutamine-Binding Protein, and (c) folding processes of the B domain of Staphylococcus aureus Protein A. All demonstrations numerically proved that the modified TBSA reproduced these biologically relevant rare events with nanosecond-order simulation times, although a set of microsecond-order, canonical MD simulations failed to reproduce the rare events, indicating the high efficiency of the modified TBSA.

  16. Prognostic value and in vitro biological relevance of Neuropilin 1 and Neuropilin 2 in osteosarcoma.

    Science.gov (United States)

    Boro, Aleksandar; Arlt, Matthias Je; Lengnick, Harald; Robl, Bernhard; Husmann, Maren; Bertz, Josefine; Born, Walter; Fuchs, Bruno

    2015-01-01

    Neoadjuvant chemotherapy in osteosarcoma increased the long-term survival of patients with localized disease considerably but metastasizing osteosarcoma remained largely treatment resistant. Neuropilins, transmembrane glycoproteins, are important receptors for VEGF dependent hyper-vascularization in tumor angiogenesis and their aberrant expression promotes tumorigenesis and metastasis in many solid tumors. Our analysis of Neuropilin-1 (NRP1) and Neuropilin-2 (NRP2) immunostaining in a tissue microarray of 66 osteosarcoma patients identified NRP2 as an indicator of poor overall, metastasis-free and progression free survival while NRP1 had no predictive value. Patients with tumors that expressed NRP2 in the absence of NRP1 had a significantly worse prognosis than NRP1(-)/NRP2(-), NRP1(+) or NRP1(+)/NRP2(+) tumors. Moreover, patients with overt metastases and with NRP2-positive primary tumors had a significantly shorter survival rate than patients with metastases but NRP2-negative tumors. Furthermore, the expression of both NRP1 and NRP2 in osteosarcoma cell lines correlated to a variable degree with the metastatic potential of the respective cell line. To address the functional relevance of Neuropilins for VEGF signaling we used shRNA mediated down-regulation and blocking antibodies of NRP1 and NRP2 in the metastatic 143B and HuO9-M132 cell lines. In 143B cells, VEGFA signaling monitored by AKT phosphorylation was more inhibited by blocking of NRP1, whereas in HuO9-M132 cells NRP2 blocking was more effective indicating that NRP1 and NRP2 can substitute each other in the functional interaction with VEGFR1. Altogether, these data point to NRP2 as a powerful prognostic marker in osteosarcoma and together with NRP1 as a novel target for tumor-suppressive therapy.

  17. Copper isotope fractionation between aqueous compounds relevant to low temperature geochemistry and biology

    Science.gov (United States)

    Fujii, Toshiyuki; Moynier, Frédéric; Abe, Minori; Nemoto, Keisuke; Albarède, Francis

    2013-06-01

    Isotope fractionation between the common Cu species present in solution (Cu+, Cu2+, hydroxide, chloride, sulfide, carbonate, oxalate, and ascorbate) has been investigated using both ab initio methods and experimental solvent extraction techniques. In order to establish unambiguously the existence of equilibrium isotope fractionation (as opposed to kinetic isotope fractionation), we first performed laboratory-scale liquid-liquid distribution experiments. Upon exchange between HCl medium and a macrocyclic complex, the 65Cu/63Cu ratio fractionated by -1.06‰ to -0.39‰. The acidity dependence of the fractionation was appropriately explained by ligand exchange reactions between hydrated H2O and Cl- via intramolecular vibrations. The magnitude of the Cu isotope fractionation among important Cu ligands was also estimated by ab initio methods. The magnitude of the nuclear field shift effect to the Cu isotope fractionation represents only ˜3% of the mass-dependent fractionation. The theoretical estimation was expanded to chlorides, hydroxides, sulfides, sulfates, and carbonates under different conditions of pH. Copper isotope fractionation of up to 2‰ is expected for different forms of Cu present in seawater and for different sediments (carbonates, hydroxides, and sulfides). We found that Cu in dissolved carbonates and sulfates is isotopically much heavier (+0.6‰) than free Cu. Isotope fractionation of Cu in hydroxide is minimal. The relevance of these new results to the understanding of metabolic processes was also discussed. Copper is an essential element used by a large number of proteins for electron transfer. Further theoretical estimates of δ65Cu in hydrated Cu(I) and Cu(II) ions, Cu(II) ascorbates, and Cu(II) oxalate predict Cu isotope fractionation during the breakdown of ascorbate into oxalate and account for the isotopically heavy Cu found in animal kidneys.

  18. The Relevance of Chromosome Aberration Yields for Biological Dosimetry After Low-Level Occupational Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bauchinger, M.; Schmid, E.; Hug, O. [Gesellschaft fuer Strahlenforschung, Institut fuer Biologie, Neuherberg, Federal Republic of Germany (Germany); Strahlenbiologisches Institut der Universitaet Muenchen, Federal Republic of Germany (Germany)

    1971-06-15

    The usefulness of chromosome analysis for biological dosimetry has been tested in two groups of persons occupationally exposed to radiation: (I) in nurses employed in gynaecological radiology, exposed especially when handling radium inserts; and (II) in nuclear industry workers, all of which were exposed to external gamma irradiation and some of them also to internal radiation after incorporation of various radionuclides. The total dose registered with personal dosimeters ranged in Group 1 from 0.1 to 91.1 rem accumulated over working periods of 0.1 to 13 years, and in Group II from 1.0 to 18.2 rem accumulated over 1 to 9 years. Compared with unexposed controls, both groups exhibit a significant increase of cells with chromosome aberrations as well as larger numbers of breaks per cell. Dicentrics and rings could be observed in some cells, providing good evidence for previous radiation exposure, since these types of aberrations are extremely rare events in unexposed individuals. No correlation between the aberration yields and the film badge values could be demonstrated in Group II. Also, in Group I the fluctuations from individual to individual are rather high. Nevertheless, a positive correlation to the ''dose'' was obtained. Even a sub-group of the nurses that had only been exposed to 20 rem showed significantly more aberrations than control persons. From the results obtained, type and frequency of chromosome aberrations may be considered an indicator of radiation exposure even at the low doses. The reasons for lack of correspondence of chromosome aberration yields and the results of personal monitoring procedures are discussed in detail. (author)

  19. Biological Effects of Osteoblast-Like Cells on Nanohydroxyapatite Particles at a Low Concentration Range

    Directory of Open Access Journals (Sweden)

    Xiaochen Liu

    2011-01-01

    Full Text Available The biological effects of osteoblast-like MG-63 cells on nanohydroxyapatite (n-HA at the low concentration range (5–25 g/mL for 5 days was investigated. The results showed the viability and actin cytoskeleton of the cells descended with the increase of the concentration of n-HA, and the actin cytoskeleton of cells was depolymerised and became more disordered. Apoptotic rate of cells (1.85%, 1.99%, and 2.29% increased with the increase of n-HA concentration (5, 15, and 25 g/mL and become significantly higher than the control. Total intracellular protein content decreased with n-HA concentration increase, showing significant difference between 25 g/mL and the control, and no significant change of ALP activity was observed at the 5th day. The results revealed that the cell growth was inhibited by n-HA in a concentration-dependent manner, and the obvious biological effects of MG-63 cells on n-HA existed at the low concentration range from 5 to 25 g/mL.

  20. A meta-analysis of the abscopal effect in preclinical models: Is the biologically effective dose a relevant physical trigger?

    Directory of Open Access Journals (Sweden)

    Raffaella Marconi

    Full Text Available Preclinical in vivo studies using small animals are considered crucial in translational cancer research and clinical implementation of novel treatments. This is of paramount relevance in radiobiology, especially for any technological developments permitted to deliver high doses in single or oligo-fractionated regimens, such as stereotactic ablative radiotherapy (SABR. In this context, clinical success in cancer treatment needs to be guaranteed, sparing normal tissue and preventing the potential spread of disease or local recurrence. In this work we introduce a new dose-response relationship based on relevant publications concerning preclinical models with regard to delivered dose, fractionation schedule and occurrence of biological effects on non-irradiated tissue, abscopal effects.We reviewed relevant publications on murine models and the abscopal effect in radiation cancer research following PRISMA methodology. In particular, through a log-likelihood method, we evaluated whether the occurrence of abscopal effects may be related to the biologically effective dose (BED. To this aim, studies accomplished with different tumor histotypes were considered in our analysis including breast, colon, lung, fibrosarcoma, pancreas, melanoma and head and neck cancer. For all the tumors, the α / β ratio was assumed to be 10 Gy, as generally adopted for neoplastic cells.Our results support the hypothesis that the occurrence rate of abscopal effects in preclinical models increases with BED. In particular, the probability of revealing abscopal effects is 50% when a BED of 60 Gy is generated.Our study provides evidence that SABR treatments associated with high BEDs could be considered an effective strategy in triggering the abscopal effect, thus shedding light on the promising outcomes revealed in clinical practice.

  1. Behavior toxicity to Caenorhabditis elegans transferred to the progeny after exposure to sulfamethoxazole at environmentally relevant concentrations

    Institute of Scientific and Technical Information of China (English)

    Zhenyang Yu; Lei Jiang; Daqiang Yin

    2011-01-01

    Sulfamethoxazole (SMX) is one of the most common detected antibiotics in the environment. In order to study whether SMX can affect behavior and growth and whether these effects could be transferred to the progeny, Caenorhabditis elegans was exposed at environmentally relevant concentrations for 24, 48, 72 and 96 hr, respectively. After exposure, the exposed parent generation (Po) was measured for behavior and growth indicators, which were presented as percentage of controls (POC). Then their corresponding unexposed progeny (F1) was separated and measured for the same indicators. The lowest POC for Po after 96 hr-exposure at 100 mg/L were 37.8%, 12.7%, 45.8% and 70.1% for body bending frequency (BBF), reversal movement (RM), Omega turns (OT) and body length (BL), respectively. And F1 suffered defects with the lowest POC as 55.8%, 24.1%, 48.5% and 60.7% for BBF, RM, OT and BL, respectively. Defects in both Po and F1 showed a time- and concentration-dependent fashion and behavior indicators showed better sensitivity than growth indicator. The observed effects on F1 demonstrated the transferable properties of SMX. Defects of SMX at environmental concentrations suggested that it is necessary to perform further systematical studies on its ecological risk in actual conditions.

  2. An electron microscopy based method for the detection and quantification of nanomaterial number concentration in environmentally relevant media

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, A. [School of Geography, Earth and Environmental Sciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Lead, J.R., E-mail: jlead@mailbox.sc.edu [School of Geography, Earth and Environmental Sciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia 29208, SC (United States); Baalousha, M., E-mail: mbaalous@mailbox.sc.edu [Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia 29208, SC (United States)

    2015-12-15

    Improved detection and characterization of nanomaterials (NMs) in complex environmental media requires the development of novel sampling approaches to improve the detection limit to be close to environmentally realistic concentrations. Transmission electron microscopy (TEM) is an indispensable metrological tool in nanotechnology and environmental nanoscience due to its high spatial resolution and analytical capabilities when coupled to spectroscopic techniques. However, these capabilities are hampered by the conventional sample preparation methods, which suffer from low NM recovery. The current work presents a validated, fully quantitative sampling technique for TEM that overcomes conventional sample preparation shortcomings, and thus enables the use of TEM for measurement of particle number concentration and their detection in complex media at environmentally realistic concentrations. This sampling method is based on ultracentrifugation of NMs from suspension onto a poly-L-lysine (PLL) functionalized TEM grid, using active deposition (by ultracentrifugation) and retention (by PLL interactions with NM surface) of NMs on the substrate, enabling fully quantitative analysis. Similar analysis with AFM was satisfactory in simple media but the lack of chemical-selectivity of AFM limits its applicability for the detection of NMs in complex environmental samples. The sampling approach was validated using both citrate- and PVP-coated AuNMs in pure water, which demonstrated an even distribution of NM on the TEM grid and high NM recovery (80–100%) at environmentally relevant NM concentrations (ca. 0.20–100 μg L{sup −1}). The applicability of the sampling method to complex environmental samples was demonstrated by the quantification of particle number concentration of AuNMs in EPA soft water (with and without Suwannee River fulvic acid) and lake water. This sample preparation approach is also applicable to other types of NMs with some modifications (e.g. centrifugation

  3. An electron microscopy based method for the detection and quantification of nanomaterial number concentration in environmentally relevant media

    International Nuclear Information System (INIS)

    Prasad, A.; Lead, J.R.; Baalousha, M.

    2015-01-01

    Improved detection and characterization of nanomaterials (NMs) in complex environmental media requires the development of novel sampling approaches to improve the detection limit to be close to environmentally realistic concentrations. Transmission electron microscopy (TEM) is an indispensable metrological tool in nanotechnology and environmental nanoscience due to its high spatial resolution and analytical capabilities when coupled to spectroscopic techniques. However, these capabilities are hampered by the conventional sample preparation methods, which suffer from low NM recovery. The current work presents a validated, fully quantitative sampling technique for TEM that overcomes conventional sample preparation shortcomings, and thus enables the use of TEM for measurement of particle number concentration and their detection in complex media at environmentally realistic concentrations. This sampling method is based on ultracentrifugation of NMs from suspension onto a poly-L-lysine (PLL) functionalized TEM grid, using active deposition (by ultracentrifugation) and retention (by PLL interactions with NM surface) of NMs on the substrate, enabling fully quantitative analysis. Similar analysis with AFM was satisfactory in simple media but the lack of chemical-selectivity of AFM limits its applicability for the detection of NMs in complex environmental samples. The sampling approach was validated using both citrate- and PVP-coated AuNMs in pure water, which demonstrated an even distribution of NM on the TEM grid and high NM recovery (80–100%) at environmentally relevant NM concentrations (ca. 0.20–100 μg L"−"1). The applicability of the sampling method to complex environmental samples was demonstrated by the quantification of particle number concentration of AuNMs in EPA soft water (with and without Suwannee River fulvic acid) and lake water. This sample preparation approach is also applicable to other types of NMs with some modifications (e.g. centrifugation

  4. Environmentally relevant concentrations of polyethylene microplastics negatively impact the survival, growth and emergence of sediment-dwelling invertebrates.

    Science.gov (United States)

    Ziajahromi, Shima; Kumar, Anupama; Neale, Peta A; Leusch, Frederic D L

    2018-05-01

    Microplastics are a widespread environmental pollutant in aquatic ecosystems and have the potential to eventually sink to the sediment, where they may pose a risk to sediment-dwelling organisms. While the impacts of exposure to microplastics have been widely reported for marine biota, the effects of microplastics on freshwater organisms at environmentally realistic concentrations are largely unknown, especially for benthic organisms. Here we examined the effects of a realistic concentration of polyethylene microplastics in sediment on the growth and emergence of a freshwater organism Chironomus tepperi. We also assessed the influence of microplastic size by exposing C. tepperi larvae to four different size ranges of polyethylene microplastics (1-4, 10-27, 43-54 and 100-126 μm). Exposure to an environmentally relevant concentration of microplastics, 500 particles/kg sediment , negatively affected the survival, growth (i.e. body length and head capsule) and emergence of C. tepperi. The observed effects were strongly dependent on microplastic size with exposure to particles in the size range of 10-27 μm inducing more pronounced effects. While growth and survival of C. tepperi were not affected by the larger microplastics (100-126 μm), a significant reduction in the number of emerged adults was observed after exposure to the largest microplastics, with the delayed emergence attributed to exposure to a stressor. While scanning electron microscopy showed a significant reduction in the size of the head capsule and antenna of C. tepperi exposed to microplastics in the 10-27 μm size range, no deformities to the external structure of the antenna and mouth parts in organisms exposed to the same size range of microplastics were observed. These results indicate that environmentally relevant concentrations of microplastics in sediment induce harmful effects on the development and emergence of C. tepperi, with effects greatly dependent on particle size. Copyright

  5. Enrofloxacin at environmentally relevant concentrations enhances uptake and toxicity of cadmium in the earthworm Eisenia fetida in farm soils

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yinsheng, E-mail: yinshengli@sjtu.edu.cn [School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240 (China); Tang, Hao; Hu, Yingxiu; Wang, Xiuhong; Ai, Xiaojie; Tang, Li [School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240 (China); Matthew, Cory [Institute of Agriculture & Environment, Massey University, Private Bag 11-222, Palmerston North 4442 (New Zealand); Cavanagh, Jo [Landcare Research, PO Box 40, Lincoln 7640 (New Zealand); Qiu, Jiangping [School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2016-05-05

    Highlights: • Enrofloxacin (EF) and cadmium (Cd) were independently adsorbed in soils. • EF accelerated and increased Cd bioaccumulation in earthworms. • At high concentration EF (10 mg kg{sup −1}) was toxic to earthworms. • EF enhanced Cd induced oxidative stress, and increased burrowing and respiration. • EF did not affect the Cd induced increase in metallothionein in earthworms. - Abstract: Individual and combined effects of enrofloxacin (EF) and cadmium (Cd) on the earthworm Eisenia fetida at environmentally relevant concentrations were investigated. EF is a veterinary antibiotic; Cd is an impurity in phosphatic fertiliser. For both, residues may accumulate in farm soils. In laboratory tests, over 98% of spiked EF was adsorbed by farm soils, with a half-life >8 weeks. However, earthworms absorbed less than 20% of spiked EF. Earthworms in soil with EF concentration 10 mg kg{sup −1} soil experienced transient oxidative stress and exhibited reduced burrowing activity and respiration after an 8-week exposure; EF at 0.1 and 1.0 mg kg{sup −1} soil did not elicit toxicity symptoms. When both were added, Cd did not affect EF uptake, but each increment of spiked EF increased Cd bioaccumulation and associated oxidative stress of earthworms, and also caused decreased burrow length and CO{sub 2} production. However, metallothionein induction was not affected. The enhanced toxicity of Cd to earthworms in the presence of EF at low environmental concentrations may have implications for the health and reproductive success of earthworm populations and highlights the importance of understanding effects of antibiotic contamination of farm soils, and of awareness of environmental effects from interaction between multiple contaminants.

  6. Enrofloxacin at environmentally relevant concentrations enhances uptake and toxicity of cadmium in the earthworm Eisenia fetida in farm soils

    International Nuclear Information System (INIS)

    Li, Yinsheng; Tang, Hao; Hu, Yingxiu; Wang, Xiuhong; Ai, Xiaojie; Tang, Li; Matthew, Cory; Cavanagh, Jo; Qiu, Jiangping

    2016-01-01

    Highlights: • Enrofloxacin (EF) and cadmium (Cd) were independently adsorbed in soils. • EF accelerated and increased Cd bioaccumulation in earthworms. • At high concentration EF (10 mg kg"−"1) was toxic to earthworms. • EF enhanced Cd induced oxidative stress, and increased burrowing and respiration. • EF did not affect the Cd induced increase in metallothionein in earthworms. - Abstract: Individual and combined effects of enrofloxacin (EF) and cadmium (Cd) on the earthworm Eisenia fetida at environmentally relevant concentrations were investigated. EF is a veterinary antibiotic; Cd is an impurity in phosphatic fertiliser. For both, residues may accumulate in farm soils. In laboratory tests, over 98% of spiked EF was adsorbed by farm soils, with a half-life >8 weeks. However, earthworms absorbed less than 20% of spiked EF. Earthworms in soil with EF concentration 10 mg kg"−"1 soil experienced transient oxidative stress and exhibited reduced burrowing activity and respiration after an 8-week exposure; EF at 0.1 and 1.0 mg kg"−"1 soil did not elicit toxicity symptoms. When both were added, Cd did not affect EF uptake, but each increment of spiked EF increased Cd bioaccumulation and associated oxidative stress of earthworms, and also caused decreased burrow length and CO_2 production. However, metallothionein induction was not affected. The enhanced toxicity of Cd to earthworms in the presence of EF at low environmental concentrations may have implications for the health and reproductive success of earthworm populations and highlights the importance of understanding effects of antibiotic contamination of farm soils, and of awareness of environmental effects from interaction between multiple contaminants.

  7. Biological treatment of concentrated hazardous, toxic, and radionuclide mixed wastes without dilution

    International Nuclear Information System (INIS)

    Stringfellow, William T.; Komada, Tatsuyuki; Chang, Li-Yang

    2004-01-01

    Approximately 10 percent of all radioactive wastes produced in the U. S. are mixed with hazardous or toxic chemicals and therefore can not be placed in secure land disposal facilities. Mixed wastes containing hazardous organic chemicals are often incinerated, but volatile radioactive elements are released directly into the biosphere. Some mixed wastes do not currently have any identified disposal option and are stored locally awaiting new developments. Biological treatment has been proposed as a potentially safer alternative to incineration for the treatment of hazardous organic mixed wastes, since biological treatment would not release volatile radioisotopes and the residual low-level radioactive waste would no longer be restricted from land disposal. Prior studies have shown that toxicity associated with acetonitrile is a significant limiting factor for the application of biotreatment to mixed wastes and excessive dilution was required to avoid inhibition of biological treatment. In this study, we demonstrate that a novel reactor configuration, where the concentrated toxic waste is drip-fed into a complete-mix bioreactor containing a pre-concentrated active microbial population, can be used to treat a surrogate acetonitrile mixed waste stream without excessive dilution. Using a drip-feed bioreactor, we were able to treat a 90,000 mg/L acetonitrile solution to less than 0.1 mg/L final concentration using a dilution factor of only 3.4. It was determined that the acetonitrile degradation reaction was inhibited at a pH above 7.2 and that the reactor could be modeled using conventional kinetic and mass balance approaches. Using a drip-feed reactor configuration addresses a major limiting factor (toxic inhibition) for the biological treatment of toxic, hazardous, or radioactive mixed wastes and suggests that drip-feed bioreactors could be used to treat other concentrated toxic waste streams, such as chemical warfare materiel

  8. Biological treatment of concentrated hazardous, toxic, andradionuclide mixed wastes without dilution

    Energy Technology Data Exchange (ETDEWEB)

    Stringfellow, William T.; Komada, Tatsuyuki; Chang, Li-Yang

    2004-06-15

    Approximately 10 percent of all radioactive wastes produced in the U. S. are mixed with hazardous or toxic chemicals and therefore can not be placed in secure land disposal facilities. Mixed wastes containing hazardous organic chemicals are often incinerated, but volatile radioactive elements are released directly into the biosphere. Some mixed wastes do not currently have any identified disposal option and are stored locally awaiting new developments. Biological treatment has been proposed as a potentially safer alternative to incineration for the treatment of hazardous organic mixed wastes, since biological treatment would not release volatile radioisotopes and the residual low-level radioactive waste would no longer be restricted from land disposal. Prior studies have shown that toxicity associated with acetonitrile is a significant limiting factor for the application of biotreatment to mixed wastes and excessive dilution was required to avoid inhibition of biological treatment. In this study, we demonstrate that a novel reactor configuration, where the concentrated toxic waste is drip-fed into a complete-mix bioreactor containing a pre-concentrated active microbial population, can be used to treat a surrogate acetonitrile mixed waste stream without excessive dilution. Using a drip-feed bioreactor, we were able to treat a 90,000 mg/L acetonitrile solution to less than 0.1 mg/L final concentration using a dilution factor of only 3.4. It was determined that the acetonitrile degradation reaction was inhibited at a pH above 7.2 and that the reactor could be modeled using conventional kinetic and mass balance approaches. Using a drip-feed reactor configuration addresses a major limiting factor (toxic inhibition) for the biological treatment of toxic, hazardous, or radioactive mixed wastes and suggests that drip-feed bioreactors could be used to treat other concentrated toxic waste streams, such as chemical warfare materiel.

  9. Cystatin C and lactoferrin concentrations in biological fluids as possible prognostic factors in eye tumor development

    Directory of Open Access Journals (Sweden)

    Mariya A. Dikovskaya

    2013-08-01

    Full Text Available Objectives. To investigate the possible role of cystatin C in eye biological fluids locally and in serum and lactoferrin revealing anti-tumor activity in eye tumor development. Background. The increased number of eye tumors was registered recently not only in the countries with high insolation, but also in the northern countries including Russia (11 cases per million of population. Search for new biological markers is important for diagnosis and prognosis in eye tumors. Cystatin C, an endogenous inhibitor of cysteine proteases, plays an important protective role in several tumors. Lactoferrin was shown to express anti-tumor and antiviral activities. It was hypothesized that cystatin C and lactoferrin could serve as possible biomarkers in the diagnosis of malignant and benign eye tumors. Study design. A total of 54 patients with choroidal melanoma and benign eye tumors were examined (part of them undergoing surgical treatment. Serum, tear fluid and intraocular fluid samples obtained from the anterior chamber of eyes in patients with choroidal melanoma were studied. Methods. Cystatin C concentration in serum and eye biological fluids was measured by commercial ELISA kits for human (BioVendor, Czechia; lactoferrin concentration – by Lactoferrin-strip D 4106 ELISA test systems (Vector-BEST, Novosibirsk Region, Russia. Results. Cystatin C concentration in serum of healthy persons was significantly higher as compared to tear and intraocular fluids. In patients with choroidal melanoma, increased cystatin C concentration was similar in tear fluid of both the eyes. Lactoferrin level in tear fluid of healthy persons was significantly higher than its serum level. Significantly increased lactoferrin concentration in tear fluid was noted in patients with benign and malignant eye tumors. Conclusion. Increased level of cystatin C in tear fluid seems to be a possible diagnostic factor in the eye tumors studied. However, it does not allow us to differentiate

  10. Detection of base damage in DNA in human blood exposed to ionizing radiation at biologically relevant doses

    International Nuclear Information System (INIS)

    Loon, A.A.W.M. van; Lohman, P.H.M.; Groenendijk, R.H.; Schans, G.P. van der; Baan, R.A.

    1991-01-01

    The alkaline elution technique for the detection of DNA damage has been adapted to allow application on unlabelled blood cells. Both the induction and subsequent repair have been studied of two classes of DNA damage, viz. single-strand breaks and base damage recognized by the γ-endonuclease activity in a cell-free extract of Micrococcus luteus bacteria. The high sensitivity of the assay permitted the measurement of induction and repair of base damage after in vitro exposure of full blood under aerobic conditions to biologically relevant doses of γ-rays (1.5-4.5 Gy). After a radiation dose of 3 Gy about 50% of the base damage was removed within 1.5 h of repair. Base damage could still be detected at 24h after exposure to 15 Gy. (author)

  11. Regulation of NF-κB activity in astrocytes: effects of flavonoids at dietary-relevant concentrations

    International Nuclear Information System (INIS)

    Spilsbury, Alison; Vauzour, David; Spencer, Jeremy P.E.; Rattray, Marcus

    2012-01-01

    Highlights: ► We tested the hypothesis that low concentrations of flavonoids inhibit NF-κB in astrocytes. ► Primary cultured astrocytes possess a functional κB-system, measured using luciferase assays. ► Seven flavonoids (100 nM–1 μM) failed to reduce NF-κB activity in astrocytes. ► Four flavonoids (100 nM–1 μM) failed to reduce TNFa-stimulated NF-κB activity in astrocytes. ► (−)-Epicatechin did not regulate nuclear translocation of the NF-κB subunit, p65. -- Abstract: Neuroinflammation plays an important role in the progression of neurodegenerative disorders such as Alzheimer’s disease and Parkinson’s disease. Sustained activation of nuclear transcription factor κB (NF-κB) is thought to play an important role in the pathogenesis of neurodegenerative disorders. Flavonoids have been shown to possess antioxidant and anti-inflammatory properties and we investigated whether flavonoids, at submicromolar concentrations relevant to their bioavailability from the diet, were able to modulate NF-κB signalling in astrocytes. Using luciferase reporter assays, we found that tumour necrosis factor (TNFα, 150 ng/ml) increased NF-κB-mediated transcription in primary cultures of mouse cortical astrocytes, which was abolished on co-transfection of a dominant-negative IκBα construct. In addition, TNFα increased nuclear localisation of p65 as shown by immunocytochemistry. To investigate potential flavonoid modulation of NF-κB activity, astrocytes were treated with flavonoids from different classes; flavan-3-ols ((−)-epicatechin and (+)-catechin), flavones (luteolin and chrysin), a flavonol (kaempferol) or the flavanones (naringenin and hesperetin) at dietary-relevant concentrations (0.1–1 μM) for 18 h. None of the flavonoids modulated constitutive or TNFα-induced NF-κB activity. Therefore, we conclude that NF-κB signalling in astrocytes is not a major target for flavonoids.

  12. Regulation of NF-{kappa}B activity in astrocytes: effects of flavonoids at dietary-relevant concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Spilsbury, Alison [Reading School of Pharmacy, University of Reading, Reading RG6 6UB (United Kingdom); Vauzour, David; Spencer, Jeremy P.E. [Molecular Nutrition Group, Centre for Integrative Neuroscience and Neurodynamics, School of Chemistry, Food and Pharmacy, University of Reading, Reading RG6 6AP (United Kingdom); Rattray, Marcus, E-mail: m.a.n.rattray@reading.ac.uk [Reading School of Pharmacy, University of Reading, Reading RG6 6UB (United Kingdom)

    2012-02-17

    Highlights: Black-Right-Pointing-Pointer We tested the hypothesis that low concentrations of flavonoids inhibit NF-{kappa}B in astrocytes. Black-Right-Pointing-Pointer Primary cultured astrocytes possess a functional {kappa}B-system, measured using luciferase assays. Black-Right-Pointing-Pointer Seven flavonoids (100 nM-1 {mu}M) failed to reduce NF-{kappa}B activity in astrocytes. Black-Right-Pointing-Pointer Four flavonoids (100 nM-1 {mu}M) failed to reduce TNFa-stimulated NF-{kappa}B activity in astrocytes. Black-Right-Pointing-Pointer (-)-Epicatechin did not regulate nuclear translocation of the NF-{kappa}B subunit, p65. -- Abstract: Neuroinflammation plays an important role in the progression of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Sustained activation of nuclear transcription factor {kappa}B (NF-{kappa}B) is thought to play an important role in the pathogenesis of neurodegenerative disorders. Flavonoids have been shown to possess antioxidant and anti-inflammatory properties and we investigated whether flavonoids, at submicromolar concentrations relevant to their bioavailability from the diet, were able to modulate NF-{kappa}B signalling in astrocytes. Using luciferase reporter assays, we found that tumour necrosis factor (TNF{alpha}, 150 ng/ml) increased NF-{kappa}B-mediated transcription in primary cultures of mouse cortical astrocytes, which was abolished on co-transfection of a dominant-negative I{kappa}B{alpha} construct. In addition, TNF{alpha} increased nuclear localisation of p65 as shown by immunocytochemistry. To investigate potential flavonoid modulation of NF-{kappa}B activity, astrocytes were treated with flavonoids from different classes; flavan-3-ols ((-)-epicatechin and (+)-catechin), flavones (luteolin and chrysin), a flavonol (kaempferol) or the flavanones (naringenin and hesperetin) at dietary-relevant concentrations (0.1-1 {mu}M) for 18 h. None of the flavonoids modulated constitutive or

  13. On making nursing undergraduate human reproductive physiology content meaningful and relevant: discussion of human pleasure in its biological context.

    Science.gov (United States)

    McClusky, Leon Mendel

    2012-01-01

    The traditional presentation of the Reproductive Physiology component in an Anatomy and Physiology course to nursing undergraduates focuses on the broad aspects of hormonal regulation of reproduction and gonadal anatomy, with the role of the higher centres of the brain omitted. An introductory discussion is proposed which could precede the lectures on the reproductive organs. The discussion gives an overview of the biological significance of human pleasure, the involvement of the neurotransmitter dopamine, and the role of pleasure in the survival of the individual and even species. Pleasure stimuli (positive and negative) and the biological significance of naturally-induced pleasurable experiences are briefly discussed in the context of reproduction and the preservation of genetic material with an aim to foster relevancy between subject material and human behaviour in any type of society. The tenderness of this aspect of the human existence is well-understood because of its invariable association with soul-revealing human expressions such as love, infatuation, sexual flirtations, all of which are underpinned by arousal, desire and/or pleasure. Assuming that increased knowledge correlates with increased confidence, the proposed approach may provide the nurse with an adequate knowledge base to overcome well-known barriers in communicating with their patients about matters of sexual health and intimacy. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. [Effect of different oxygen concentrations on biological properties of bone marrow hematopoietic stem cells of mice].

    Science.gov (United States)

    Ma, Yi-Ran; Ren, Si-Hua; He, Yu-Xin; Wang, Lin-Lin; Jin, Li; Hao, Yi-Wen

    2012-10-01

    This study purposed to investigate the effects of different oxygen concentrations and reactive oxygen species (ROS) on the biological characteristics of hematopoietic stem cells (HSC) and their possible mechanisms through simulating oxygen environment to which the peripheral blood HSC are subjected in peripheral blood HSCT. The proliferation ability, cell cycle, directed differentiation ability, ROS level and hematopoietic reconstitution ability of Lin(-)c-kit(+)Sca-1(+) BMHSC were detected by using in vitro amplification test, directional differentiation test, cell cycle analysis, ROS assay and transplantation of Lin(-)c-kit(+)Sca-1(+) HSC from sublethally irradiated mice respectively. The results showed that oxygen concentrations lower than normal oxygen concentration, especially in hypoxic oxygen environment, could reduce ROS generation and amplify more primitive CD34(+)AC133(+) HSC and active CD34(+) HSC, and maintain more stem cells in the G(0)/G(1) phase, which is more helpful to the growth of CFU-S and viability of mice. At the same time, BMHSC exposed to normal oxygen level or inconstant and greatly changed oxygen concentrations could produce a high level of ROS, and the above-mentioned features and functional indicators are relatively low. It is concluded that ROS levels of HSC in BMHSCT are closely related with the oxygen concentration surrounding the cells and its stability. Low oxygen concentration and antioxidant intervention are helpful to transplantation of BMHSC.

  15. Biological effects of tritium on fish cells in the concentration range of international drinking water standards.

    Science.gov (United States)

    Stuart, Marilyne; Festarini, Amy; Schleicher, Krista; Tan, Elizabeth; Kim, Sang Bog; Wen, Kendall; Gawlik, Jilian; Ulsh, Brant

    2016-10-01

    To evaluate whether the current Canadian tritium drinking water limit is protective of aquatic biota, an in vitro study was designed to assess the biological effects of low concentrations of tritium, similar to what would typically be found near a Canadian nuclear power station, and higher concentrations spanning the range of international tritium drinking water standards. Channel catfish peripheral blood B-lymphoblast and fathead minnow testis cells were exposed to 10-100,000 Bq l(-1) of tritium, after which eight molecular and cellular endpoints were assessed. Increased numbers of DNA strand breaks were observed and ATP levels were increased. There were no increases in γH2AX-mediated DNA repair. No differences in cell growth were noted. Exposure to the lowest concentrations of tritium were associated with a modest increase in the viability of fathead minnow testicular cells. Using the micronucleus assay, an adaptive response was observed in catfish B-lymphoblasts. Using molecular endpoints, biological responses to tritium in the range of Canadian and international drinking water standards were observed. At the cellular level, no detrimental effects were noted on growth or cycling, and protective effects were observed as an increase in cell viability and an induced resistance to a large challenge dose.

  16. The progestin norethisterone affects thyroid hormone-dependent metamorphosis of Xenopus laevis tadpoles at environmentally relevant concentrations.

    Science.gov (United States)

    Lorenz, Claudia; Krüger, Angela; Schöning, Viola; Lutz, Ilka

    2018-04-15

    Previously, levonorgestrel (LNG) has been shown to be an endocrine disruptor of the amphibian thyroid system. In the present study, we investigated whether anti-thyroidal effects are a common property of progestins other than LNG. Premetamorphic Xenopus laevis tadpoles were exposed to norethisterone (NET) and dienogest DIE (each at 0.1-10nM) and LNG (10nM) until completion of metamorphosis. LNG and NET at all concentrations caused a significant developmental retardation whereas DIE did not impair time to metamorphosis. In LNG and 10nM NET exposed animals, tsh mRNA levels increased considerably later than the developmental delay occurred and thyroid histopathology showed no signs of TSH-hyperstimulation. Instead, thyroid glands from these treatments appeared inactive in producing thyroid hormones. Thyroidal transcript levels of dio2 and dio3 were increased by treatments with LNG and NET at 1nM and 10nM, whereas iyd mRNA was reduced by LNG and 10nM NET. Expression of slc5α5 was not changed by any treatment. Effects of DIE differed from those induced by LNG and NET. No developmental delay was measurable; however, tshβ and dio2 mRNAs were increased in pituitary glands of tadpoles exposed to 1.0nM and 10nM DIE. Thyroid histopathology displayed no abnormalities and thyroidal mRNA expression of the genes analyzed (slc5α5, iyd, dio2, dio3) was not changed by DIE. Overall, our results provide evidence that the anti-thyroidal effects already known from LNG are also present in another progestin, namely NET, even at environmentally relevant concentrations. In conclusion we suggest that progestins do not only pose an environmental risk in terms of their impact on reproductive success of aquatic vertebrates, but also with respect to their anti-thyroidal properties affecting amphibian metamorphosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Concentration and characteristics of depleted uranium in biological and water samples collected in Bosnia and Herzegovina

    International Nuclear Information System (INIS)

    Jia Guogang; Belli, Maria; Sansone, Umberto; Rosamilia, Silvia; Gaudino, Stefania

    2006-01-01

    During Balkan conflicts in 1994-1995, depleted uranium (DU) ordnance was employed and was left in the battlefield. Health concern is related to the risk arising from contamination of the environment with DU penetrators and dust. In order to evaluate the impact of DU on the environment and population in Bosnia and Herzegovina, radiological survey of DU in biological and water samples were carried out over the period 12-24 October 2002. The uranium isotopic concentrations in biological samples collected in Bosnia and Herzegovina, mainly lichens, mosses and barks, were found to be in the range of 0.27-35.7 Bq kg -1 for 238 U, 0.24-16.8 Bq kg -1 for 234 U, and 0.02-1.11 Bq kg -1 for 235 U, showing uranium levels to be higher than in the samples collected at the control site. Moreover, the 236 U in some of the samples was detectable. The isotopic ratios of 234 U/ 238 U showed DU to be detectable in many biological samples at most sites examined, but in very low levels. The presence of DU in the biological samples was as a result of DU contamination in air. The uranium concentrations in water samples collected in Bosnia and Herzegovina were found to be in the range of 0.27-16.2 mBq l -1 for 238 U, 0.41-15.6 mBq l -1 for 234 U and 0.012-0.695 mBq l -1 for 235 U, and two water samples were observed to be DU positive; these values are much lower than those in mineral water found in central Italy and below the WHO guideline for public drinking water. From radiotoxicological point of view, at this moment there is no significant radiological risk related to these investigated sites in terms of possible DU contamination of water and/or plants

  18. Salt at concentrations relevant to meat processing enhances Shiga toxin 2 production in Escherichia coli O157:H7.

    Science.gov (United States)

    Harris, Shaun M; Yue, Wan-Fu; Olsen, Sarena A; Hu, Jia; Means, Warrie J; McCormick, Richard J; Du, Min; Zhu, Mei-Jun

    2012-10-15

    Escherichia coli (E. coli) O157:H7 remains a major food safety concern associated with meat, especially beef products. Shiga toxins (Stx) are key virulence factors produced by E. coli O157:H7 that are responsible for hemorrhagic colitis and Hemolytic Uremic Syndrome. Stx are heat stable and can be absorbed after oral ingestion. Despite the extensive study of E. coli O157:H7 survival during meat processing, little attention is paid to the production of Stx during meat processing. The objective of this study was to elucidate the effect of salt, an essential additive to processed meat, at concentrations relevant to meat processing (0%, 1%, 2%, 3%, W/V) on Stx2 production and Stx2 prophage induction by E. coli O157:H7 strains. For both E. coli O157:H7 86-24 and EDL933 strains, including 2% salt in LB broth decreased (Pmeat processing enhances Stx production, a process linked to bacterial stress response and lambdoid prophage induction. Published by Elsevier B.V.

  19. Interpretation of biological-rate coefficients derived from radionuclide content, radionuclide concentration and specific activity experiments

    International Nuclear Information System (INIS)

    Vanderploeg, H.A.; Booth, R.S.

    1976-01-01

    Rigorous expressions are derived for the biological-rate coefficients (BRCs) determined from time-dependent measurements of three different dependent variables of radionuclide tracer experiments. These variables, which apply to a single organism, are radionuclide content, radionuclide concentration and specific activity. The BRCs derived from these variables have different mathematical expressions and, for high growth rates, their numerical values can be quite different. The precise mathematical expressions for the BRCs are presented here to aid modelers in selecting the correct parameters for their models and to aid experiments in interpreting their results. The usefulness of these three variables in quantifying elemental uptakes and losses by organisms is discussed. (U.K.)

  20. Evaluation of some procedures relevant to the determination of trace elemental components in biological materials by destructive neutron activation analysis

    International Nuclear Information System (INIS)

    Berry, D.L.

    1979-01-01

    The development of a simplified procedure for the analysis of biological materials by destructive neutron activation analysis (DNAA) is described. The sample manipulations preceding gamma ray assay were investigated as five specific stages of processing: (1) pre-irradiation treatment; (2) sample irradiation; (3) removal of the organic matrix; (4) removal of interfering radioactivities; and (5) concentration and separation of analyte activities. Each stage was evaluated with respect to susceptibility to sample contamination, loss of trace elemental components, and compatibility with other operations in the overall DNAA procedures. A complete DNAA procedure was proposed and evaluated for the analysis of standard bovine liver and blood samples. The DNAA system was effective for the determination of As, Cu, Fe, Hg, Mo, Rb, Sb, Se, and Zn without yield determinations and with a minimum turn-around time of approximately 3 days

  1. Evaluation of some procedures relevant to the determination of trace elemental components in biological materials by destructive neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Berry, D.L.

    1979-01-01

    The development of a simplified procedure for the analysis of biological materials by destructive neutron activation analysis (DNAA) is described. The sample manipulations preceding gamma ray assay were investigated as five specific stages of processing: (1) pre-irradiation treatment; (2) sample irradiation; (3) removal of the organic matrix; (4) removal of interfering radioactivities; and (5) concentration and separation of analyte activities. Each stage was evaluated with respect to susceptibility to sample contamination, loss of trace elemental components, and compatibility with other operations in the overall DNAA procedures. A complete DNAA procedure was proposed and evaluated for the analysis of standard bovine liver and blood samples. The DNAA system was effective for the determination of As, Cu, Fe, Hg, Mo, Rb, Sb, Se, and Zn without yield determinations and with a minimum turn-around time of approximately 3 days.

  2. Dynamics of Intracellular Polymers in Enhanced Biological Phosphorus Removal Processes under Different Organic Carbon Concentrations

    Directory of Open Access Journals (Sweden)

    Lizhen Xing

    2013-01-01

    Full Text Available Enhanced biological phosphorus removal (EBPR may deteriorate or fail during low organic carbon loading periods. Polyphosphate accumulating organisms (PAOs in EBPR were acclimated under both high and low organic carbon conditions, and then dynamics of polymers in typical cycles, anaerobic conditions with excess organic carbons, and endogenous respiration conditions were examined. After long-term acclimation, it was found that organic loading rates did not affect the yield of PAOs and the applied low organic carbon concentrations were advantageous for the enrichment of PAOs. A low influent organic carbon concentration induced a high production of extracellular carbohydrate. During both anaerobic and aerobic endogenous respirations, when glycogen decreased to around 80 ± 10 mg C per gram of volatile suspended solids, PAOs began to utilize polyphosphate significantly. Regressed by the first-order reaction model, glycogen possessed the highest degradation rate and then was followed by polyphosphate, while biomass decay had the lowest degradation rate.

  3. The landsnail Cepaea nemoralis regulates internal Cd levels when fed on Cd-enriched stinging nettle (Urtica dioica) leaves at low, field-relevant concentrations.

    NARCIS (Netherlands)

    Notten, M.J.M.; Oosthoek, A.; Rozema, J.; Aerts, R.

    2006-01-01

    We studied Cd accumulation in Cepaea nemoralis snails at low, but field-relevant Cd concentrations in the diet (Urtica dioica leaves). Six treatments of U. dioica plants were grown, resulting in leaf Cd concentrations between 0 and 2.6 μg g

  4. Biological processes for concentrating trace elements from uranium mine waters. Technical completion report

    International Nuclear Information System (INIS)

    Brierley, C.L.; Brierley, J.A.

    1981-12-01

    Waste water from uranium mines in the Ambrosia Lake district near Grants, New Mexico, USA, contains uranium, selenium, radium and molybdenum. The Kerr-McGee Corporation has a novel treatment process for waters from two mines to reduce the concentrations of the trace contaminants. Particulates are settled by ponding, and the waters are passed through an ion exchange resin to remove uranium; barium chloride is added to precipitate sulfate and radium from the mine waters. The mine waters are subsequently passed through three consecutive algae ponds prior to discharge. Water, sediment and biological samples were collected over a 4-year period and analyzed to assess the role of biological agents in removal of inorganic trace contaminants from the mine waters. Some of the conclusions derived from this study are: (1) The concentrations of soluble uranium, selenium and molybdenum were not diminished in the mine waters by passage through the series of impoundments which constituted the mine water treatment facility. Uranium concentrations were reduced but this was due to passage of the water through an ion exchange column. (2) The particulate concentrations of the mine water were reduced at least ten-fold by passage of the waters through the impoundments. (3) The sediments were anoxic and enriched in uranium, molybdenum and selenium. The deposition of particulates and the formation of insoluble compounds were proposed as mechanisms for sediment enrichment. (4) The predominant algae of the treatment ponds were the filamentous Spirogyra and Oscillatoria, and the benthic alga, Chara. (5) Adsorptive processes resulted in the accumulation of metals in the algae cells. (6) Stimulation of sulfate reduction by the bacteria resulted in retention of molybdenum, selenium, and uranium in sediments. 1 figure, 16 tables

  5. Application of Fourier transform infrared ellipsometry to assess the concentration of biological molecules

    Science.gov (United States)

    Garcia-Caurel, Enric; Drevillon, Bernard; De Martino, Antonello; Schwartz, Laurent

    2002-12-01

    Spectroscopic ellipsometry is a noninvasive optical characterization technique mainly used in the semiconductor field to characterize bare substrates and thin films. In particular, it allows the gathering of information concerning the physical structure of the sample, such as roughness and film thickness, as well as its optical response. In the mid-infrared (IR) range each molecule exhibits a characteristic absorption fingerprint, which makes this technique chemically selective. Phase-modulated IR ellipsometry does not require a baseline correction procedure or suppression of atmospheric CO2 and water-vapor absorption bands, thus greatly reducing the subjectivity in data analysis. We have found that ellipsometric measurements of thin films, such as the solid residuals left on a plane surface after evaporation of a liquid drop containing a given compound in solution, are particularly favorable for dosing purposes because the intensity of IR absorptions shows a linear behavior along a wide range of solution concentrations of the given compound. Our aim is to illustrate with a concrete example and to justify theoretically the linearity experimentally found between radiation absorption and molecule concentration. For the example, we prepared aqueous solutions of glycogen, a molecule of huge biological importance currently tested in biochemical analyses, at concentrations ranging from 1 mg/l to 1 g/l, which correspond to those found in physiological conditions. The results of this example are promising for the application of ellipsometry for dosing purposes in biochemistry and biomedicine.

  6. Engineering Bacteria to Search for Specific Concentrations of Molecules by a Systematic Synthetic Biology Design Method.

    Science.gov (United States)

    Tien, Shin-Ming; Hsu, Chih-Yuan; Chen, Bor-Sen

    2016-01-01

    Bacteria navigate environments full of various chemicals to seek favorable places for survival by controlling the flagella's rotation using a complicated signal transduction pathway. By influencing the pathway, bacteria can be engineered to search for specific molecules, which has great potential for application to biomedicine and bioremediation. In this study, genetic circuits were constructed to make bacteria search for a specific molecule at particular concentrations in their environment through a synthetic biology method. In addition, by replacing the "brake component" in the synthetic circuit with some specific sensitivities, the bacteria can be engineered to locate areas containing specific concentrations of the molecule. Measured by the swarm assay qualitatively and microfluidic techniques quantitatively, the characteristics of each "brake component" were identified and represented by a mathematical model. Furthermore, we established another mathematical model to anticipate the characteristics of the "brake component". Based on this model, an abundant component library can be established to provide adequate component selection for different searching conditions without identifying all components individually. Finally, a systematic design procedure was proposed. Following this systematic procedure, one can design a genetic circuit for bacteria to rapidly search for and locate different concentrations of particular molecules by selecting the most adequate "brake component" in the library. Moreover, following simple procedures, one can also establish an exclusive component library suitable for other cultivated environments, promoter systems, or bacterial strains.

  7. Engineering Bacteria to Search for Specific Concentrations of Molecules by a Systematic Synthetic Biology Design Method.

    Directory of Open Access Journals (Sweden)

    Shin-Ming Tien

    Full Text Available Bacteria navigate environments full of various chemicals to seek favorable places for survival by controlling the flagella's rotation using a complicated signal transduction pathway. By influencing the pathway, bacteria can be engineered to search for specific molecules, which has great potential for application to biomedicine and bioremediation. In this study, genetic circuits were constructed to make bacteria search for a specific molecule at particular concentrations in their environment through a synthetic biology method. In addition, by replacing the "brake component" in the synthetic circuit with some specific sensitivities, the bacteria can be engineered to locate areas containing specific concentrations of the molecule. Measured by the swarm assay qualitatively and microfluidic techniques quantitatively, the characteristics of each "brake component" were identified and represented by a mathematical model. Furthermore, we established another mathematical model to anticipate the characteristics of the "brake component". Based on this model, an abundant component library can be established to provide adequate component selection for different searching conditions without identifying all components individually. Finally, a systematic design procedure was proposed. Following this systematic procedure, one can design a genetic circuit for bacteria to rapidly search for and locate different concentrations of particular molecules by selecting the most adequate "brake component" in the library. Moreover, following simple procedures, one can also establish an exclusive component library suitable for other cultivated environments, promoter systems, or bacterial strains.

  8. Clinicopathological variables of sporadic schwannomas of peripheral nerve in 291 patients and expression of biologically relevant markers.

    Science.gov (United States)

    Young, Eric D; Ingram, Davis; Metcalf-Doetsch, William; Khan, Dilshad; Al Sannaa, Ghadah; Le Loarer, Francois; Lazar, Alexander J F; Slopis, John; Torres, Keila E; Lev, Dina; Pollock, Raphael E; McCutcheon, Ian E

    2017-09-08

    OBJECTIVE While sporadic peripheral schwannomas (SPSs) are generally well treated with surgery, their biology is not well understood. Consequently, treatment options are limited. The aim of this study was to provide a comprehensive description of SPS. The authors describe clinicopathological features and treatment outcomes of patients harboring these tumors, and they assess expression of biomarkers using a clinically annotated tissue microarray. Together, these data give new insight into the biology and management of SPS. METHODS Patients presenting with a primary SPS between 1993 and 2011 (n = 291) were selected from an institutional registry to construct a clinical database. All patients underwent follow-up, and short- and long-term outcomes were assessed. Expression of relevant biomarkers was assessed using a new tissue microarray (n = 121). RESULTS SPSs were generally large (mean 5.5 cm) and frequently painful at presentation (55%). Most patients were treated with surgery (80%), the majority of whom experienced complete resolution (52%) or improvement (18%) of their symptoms. Tumors that were completely resected (85%) did not recur. Some patients experienced short-term (16%) and long-term (4%) complications postoperatively. Schwannomas expressed higher levels of platelet-derived growth factor receptor-β (2.1) than malignant peripheral nerve sheath tumors (MPNSTs) (1.5, p = 0.004) and neurofibromas (1.33, p = 0.007). Expression of human epidermal growth factor receptor-2 was greater in SPSs (0.91) than in MPNSTs (0.33, p = 0.002) and neurofibromas (0.33, p = 0.026). Epidermal growth factor receptor was expressed in far fewer SPS cells (10%) than in MPNSTs (58%, p SPSs more frequently expressed cytoplasmic survivin (66% of tumor cells) than normal nerve (46% of cells), but SPS expressed nuclear survivin in fewer tumor cells than in MPNSTs (24% and 50%, respectively; p = 0.018). CONCLUSIONS Complete resection is curative for SPS. Left untreated, however, these

  9. The landsnail Cepaea nemoralis regulates internal Cd levels when fed on Cd-enriched stinging nettle (Urtica dioica) leaves at low, field-relevant concentrations

    International Nuclear Information System (INIS)

    Notten, M.J.M.; Oosthoek, A.J.P.; Rozema, J.; Aerts, R.

    2006-01-01

    We studied Cd accumulation in Cepaea nemoralis snails at low, but field-relevant Cd concentrations in the diet (Urtica dioica leaves). Six treatments of U. dioica plants were grown, resulting in leaf Cd concentrations between 0 and 2.6 μg g -1 dw. Seven snails per treatment were fed for 38 days. Leaf Cd concentrations did not affect food consumption rates, and consequently Cd intake rates increased with increasing leaf concentrations. No differences were detected among treatments in the final soft tissue Cd concentrations and body burdens in the snails. Regression analyses showed no positive relationship between either snail Cd concentrations or body burdens and total Cd intake. This suggests a regulation of internal Cd concentrations at low food Cd concentrations. Our data suggest that Cd excretion via the mucus plays a substantial role in this regulation, in addition to Cd excretion via the faeces. Snail shells were no sinks for Cd. - Cd excretion via the mucus plays a substantial role in the regulation of C. nemoralis soft tissue Cd concentrations at low, but field-relevant Cd concentrations in the food

  10. The landsnail Cepaea nemoralis regulates internal Cd levels when fed on Cd-enriched stinging nettle (Urtica dioica) leaves at low, field-relevant concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Notten, M.J.M. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands)]. E-mail: martje.notten@ecology.falw.vu.nl; Oosthoek, A.J.P. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands); Rozema, J. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands); Aerts, R. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands)

    2006-01-15

    We studied Cd accumulation in Cepaea nemoralis snails at low, but field-relevant Cd concentrations in the diet (Urtica dioica leaves). Six treatments of U. dioica plants were grown, resulting in leaf Cd concentrations between 0 and 2.6 {mu}g g{sup -1} dw. Seven snails per treatment were fed for 38 days. Leaf Cd concentrations did not affect food consumption rates, and consequently Cd intake rates increased with increasing leaf concentrations. No differences were detected among treatments in the final soft tissue Cd concentrations and body burdens in the snails. Regression analyses showed no positive relationship between either snail Cd concentrations or body burdens and total Cd intake. This suggests a regulation of internal Cd concentrations at low food Cd concentrations. Our data suggest that Cd excretion via the mucus plays a substantial role in this regulation, in addition to Cd excretion via the faeces. Snail shells were no sinks for Cd. - Cd excretion via the mucus plays a substantial role in the regulation of C. nemoralis soft tissue Cd concentrations at low, but field-relevant Cd concentrations in the food.

  11. Predicting Subtype Selectivity for Adenosine Receptor Ligands with Three-Dimensional Biologically Relevant Spectrum (BRS-3D)

    Science.gov (United States)

    He, Song-Bing; Ben Hu; Kuang, Zheng-Kun; Wang, Dong; Kong, De-Xin

    2016-11-01

    Adenosine receptors (ARs) are potential therapeutic targets for Parkinson’s disease, diabetes, pain, stroke and cancers. Prediction of subtype selectivity is therefore important from both therapeutic and mechanistic perspectives. In this paper, we introduced a shape similarity profile as molecular descriptor, namely three-dimensional biologically relevant spectrum (BRS-3D), for AR selectivity prediction. Pairwise regression and discrimination models were built with the support vector machine methods. The average determination coefficient (r2) of the regression models was 0.664 (for test sets). The 2B-3 (A2B vs A3) model performed best with q2 = 0.769 for training sets (10-fold cross-validation), and r2 = 0.766, RMSE = 0.828 for test sets. The models’ robustness and stability were validated with 100 times resampling and 500 times Y-randomization. We compared the performance of BRS-3D with 3D descriptors calculated by MOE. BRS-3D performed as good as, or better than, MOE 3D descriptors. The performances of the discrimination models were also encouraging, with average accuracy (ACC) 0.912 and MCC 0.792 (test set). The 2A-3 (A2A vs A3) selectivity discrimination model (ACC = 0.882 and MCC = 0.715 for test set) outperformed an earlier reported one (ACC = 0.784). These results demonstrated that, through multiple conformation encoding, BRS-3D can be used as an effective molecular descriptor for AR subtype selectivity prediction.

  12. Decomposing the effects of ocean warming on chlorophyll a concentrations into physically and biologically driven contributions

    International Nuclear Information System (INIS)

    Olonscheck, D; Hofmann, M; Schellnhuber, H J; Worm, B

    2013-01-01

    Recently compiled observational data suggest a substantial decline in the global median chlorophyll a concentration over the 20th century, a trend that appears to be linked to ocean warming. Several modelling studies have considered changes in the ocean’s physical structure as a possible cause, while experimental work supports a biological mechanism, namely an observed increase in zooplankton grazing rate that outpaces phytoplankton production at higher temperatures. Here, we present transient simulations derived from a coupled ocean general circulation and carbon cycle model forced by atmospheric fields under unabated anthropogenic global warming (IPCC SRES A1FI scenario). The simulations account for both physical and biological mechanisms, and can reproduce about one quarter of the observed chlorophyll a decline during the 20th century, when using realistically parameterized temperature sensitivity of zooplankton metabolism (Q 10 between 2 and 4) and phytoplankton growth (Q 10 ∼ 1.9). Therefore, we have employed and re-calibrated the standard ecosystem model which assumes a lower temperature sensitivity of zooplankton grazing (Q 10 = 1.1049) by re-scaling phytoplankton growth rates and zooplankton grazing rates. Our model projects a global chlorophyll a decline of >50% by the end of the 21st century. While phytoplankton abundance and chlorophyll a experience pronounced negative effects, primary production and zooplankton concentrations are less sensitive to ocean warming. Although changes in physical structure play an important role, much of the simulated change in chlorophyll a and productivity is related to the uneven temperature sensitivity of the marine ecosystem. (letter)

  13. Dose addition models based on biologically-relevant reductions in fetal testosterone accurately predict postnatal reproductive tract alterations by a phthalate mixture in rats

    Science.gov (United States)

    Challenges in cumulative risk assessment of anti-androgenic phthalate mixtures include a lack of data on all the individual phthalates and difficulty determining the biological relevance of reduction in fetal testosterone (T) on postnatal development. The objectives of the curren...

  14. Biological concentration of radionuclides in plants and animals after Chernobyl catastrophe

    International Nuclear Information System (INIS)

    Nakajima, Hiroo; Ryo, Haruko; Nomura, Taisei; Yamaguchi, Yoshiaki; Saito, Tadashi; Yeliseeva, K.G.; Piskunov, V.S.; Krupnova, E.V.; Voitovich, A.M.

    2000-01-01

    The 137 Cs radioactivity and its distribution in plants (trees, mushrooms, berries, duckweed, and etc.) and animals (insects, mice, fish, and etc.) were measured in contaminated areas of southern Belarus, which was highly polluted by radionuclides as a result of the Chernobyl catastrophe in Ukraine in 1986. Gamma spectrometry of 137 Cs was carried out, and a computer graphic imaging analysis was performed to visualize the distribution of radioactive nuclides in the organisms. The specimen was placed on the imaging plate, the plate was exposed for 20 h. High 137 Cs radioactivity was detected in both the animals (mice, moles, dragonflies, grasshoppers, and fish) and the plants (pine trees, oak leaves, mushrooms, berries, duckweed). The 137 Cs radioactivity in the organisms was proportional to the radioactivity in the soil. Assessment of its distribution showed that 137 Cs was highly concentrated in muscle, but there were no substantial differences in 137 Cs radioactivity according to organ or species. Computer graphic imaging analysis clearly revealed non-uniform distribution of 137 Cs radioactivity in the animals and plants. In pine trees, the highest level of radioactivity was found in the bark, and it decreased toward the center of the tree. In conclusion, the authors suggest that self-cleaning of the soil will require a very long time and that the biological concentrations will persist and increase in higher animals for a long time, resulting in accumulation of both external and internal radiation exposure in animals. (K.H.)

  15. Determination of sup 18 O concentrations in microsamples of biological fluids

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, D D [Australian Nuclear Science and Technology Organisation (ANSTO), Menai (Australia); Bradshaw, S D; Bradshaw, F J [University of Western Australia, Perth (Australia). Dept. of Zoology; Katsaros, A [Australian Inst. of Nuclear Science and Engineering (AINSE), Menai (Australia)

    1990-04-01

    The {sup 18}O(p, {alpha}){sup 15}N reaction has been developed for the analysis of microsamples of biological fluids containing {sup 18}O-enriched water. Samples as small as 50 {mu}l have been used. Well characterized Ta{sub 2}O{sub 5} targets were prepared from these fluids and irradiated with several hundred nA of protons from the 3 MV Van de Graaff at Lucas Heights. The broad (47 keV) 846 kV resonance in this reaction was used to measure {sup 18}O concentrations down to natural backgrounds (0.2 at.%) in a few minutes of accelerator running time. Concentrations of {sup 18}O from 0 to 5 at.% were measured in body fluids in small Australian lizards directly after doping with {sup 18}O-enriched water and then again after several days of roaming around in their natural desert environments. The changes in these levels were related to the metabolic rates of these animals. (orig.).

  16. Biological treatment and toxicity of low concentrations of oily wastewater (bilgewater)

    Energy Technology Data Exchange (ETDEWEB)

    Stamper, D.M. [NAVSEA Carderrock Div., West Bethesda, MD (United States). Biological Sciences Group; Montgomery, M.T. [Naval Research Laboratory, Washington, DC (United States). Marine Biochemistry Section

    2008-08-15

    Oily waste water from ships occurs when materials leak, spill, or are washed off the decks and drain into the bilge compartments of ships. The wastes include diesel fuel, coolants, and engine, transmission, and hydraulic oils. Treatments for oily waste water in the United States Navy are based on a combination of density separation and ceramic membrane ultrafiltration techniques, which may not meet planned regulations that will require lower levels of oil pollutants. This study tested the biodegradability and toxicity of low concentrations of oily waste water in order to establish the feasibility of using a combined shipboard oily and sanitary waste water treatment system. The toxic effects of diesel fuel and other components of the waste water were also tested. The study showed that diluting the oily effluent with the sanitary waste stream resulted in waste water with low enough oil content to meet the anticipated changes in waste water regulations. The study also showed that the low concentrations of waste water were catabolized in the presence of the sanitary waste stream. A modified PolyTox assay was used to test the waste water samples. Results of the study showed that heterotrophic bacterial production rates did not show any toxic effects. The addition of detergent in the samples had no impact on toxicity levels. It was concluded that combining oil and sanitary waste water in a single biological treatment system is a feasible option for ensuring the future regulations are met. 37 refs., 2 tabs., 4 figs.

  17. Time-resolved and steady-state studies of biologically and chemically relevant systems using laser, absorption, and fluorescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, Charles Ashley [Iowa State Univ., Ames, IA (United States)

    2014-12-20

    In Chapter 2 several experimental and data analysis methods used in this thesis are described. In Chapter 3 steady-state fluorescence spectroscopy was used to determine the concentration of the efflux pump inhibitors (EPIs), pheophorbide a and pyropheophorbide a, in the feces of animals and it was found that their levels far exceed those reported to be inhibitory to efflux pumps. In Chapter 4 the solvation dynamics of 6-Propionyl-2-(N,Ndimethyl) aminonaphthalene (PRODAN) was studied in reverse micelles. The two fluorescent states of PRODAN solvate on different time scales and as such care must be exercised in solvation dynamic studies involving it and its analogs. In Chapter 5 we studied the experimental and theoretical solvation dynamics of coumarin 153 (C153) in wild-type (WT) and modified myoglobins. Based on the nuclear magnetic resonance (NMR) spectroscopy and time-resolved fluorescence studies, we have concluded that it is important to thoroughly characterize the structure of a protein and probe system before comparing the theoretical and experimental results. In Chapter 6 the photophysical and spectral properties of a derivative of the medically relevant compound curcumin called cyclocurcumin was studied. Based on NMR, fluorescence, and absorption studies, the ground- and excited-states of cyclocurcumin are complicated by the existence of multiple structural isomers. In Chapter 7 the hydrolysis of cellulose by a pure form of cellulase in an ionic liquid, HEMA, and its aqueous mixtures at various temperatures were studied with the goal of increasing the cellulose to glucose conversion for biofuel production. It was found that HEMA imparts an additional stability to cellulase and can allow for faster conversion of cellulose to glucose using a pre-treatment step in comparison to only buffer.

  18. Purification and concentration of lead samples in biological monitoring of occupational exposures

    Directory of Open Access Journals (Sweden)

    A Rahimi-Froushani

    2006-04-01

    Full Text Available Background and Aims:Lead is an important environmental constituent widely used in industrialprocesses for production of synthetic materials and therefore can be released in the environmentcausing public exposure especially around the industrial residence area. For evaluation of humanexposure to trace toxic metal of Pb (II, environmental and biological monitoring are essentialprocesses, in which, preparation of such samples is one of the most time-consuming and errorproneaspects prior to analysis. The use of solid-phase extraction (SPE has grown and is a fertiletechnique of sample preparation as it provides better results than those produced by liquid-liquidextraction (LLE. The aim of this study was to investigate factors influencing sample pretreatmentfor trace analysis of lead in biological samples for evaluation of occupational exposure.Method :To evaluate factors influencing quantitative analysis scheme of lead, solid phaseextraction using mini columns filled with XAD-4 resin was optimized with regard to sample pH,ligand concentration, loading flow rate, elution solvent, sample volume (up to 500 ml, elutionvolume, amount of resins, and sample matrix interferences.Results :Lead was retained on solid sorbent and eluted followed by simple determination ofanalytes by using flame atomic absorption spectrometery. Obtained recoveries of the metal ionwere more than 92%. The amount of the analyte detected after simultaneous pre-concentrationwas basically in agreement with the added amounts. The optimized procedure was also validatedwith three different pools of spiked urine samples and showed a good reproducibility over sixconsecutive days as well as six within-day experiments. The developed method promised to beapplicable for evaluation of other metal ions present in different environmental and occupationalsamples as suitable results were obtained for relative standard deviation (less than 10%.Conclusion:This optimized method can be considered to be

  19. Best practices for the use and exchange of invertebrate biological control genetic resources relevant for food and agriculture

    NARCIS (Netherlands)

    Mason, P.G.; Cock, M.J.W.; Barratt, B.I.P.; Klapwijk, J.N.; Lenteren, van J.C.; Brodeur, J.; Hoelmer, K.A.; Heimpel, G.E.

    2018-01-01

    The Nagoya Protocol is a supplementary agreement to the Convention on Biological Diversity that provides a framework for the effective implementation of the fair and equitable sharing of benefits arising out of the utilization of genetic resources, including invertebrate biological control agents.

  20. New mescaline concentrations from 14 taxa/cultivars of Echinopsis spp. (Cactaceae) ("San Pedro") and their relevance to shamanic practice.

    Science.gov (United States)

    Ogunbodede, Olabode; McCombs, Douglas; Trout, Keeper; Daley, Paul; Terry, Martin

    2010-09-15

    The aim of the present study is to determine in a procedurally uniform manner the mescaline concentrations in stem tissue of 14 taxa/cultivars of the subgenus Trichocereus of the genus Echinopsis (Cactaceae) and to evaluate the relationship (if any) between mescaline concentration and actual shamanic use of these plants. Columnar cacti of the genus Echinopsis, some of which are used for diagnostic and therapeutic purposes by South American shamans in traditional medicine, were selected for analysis because they were vegetative clones of plants of documented geographic origin and/or because they were known to be used by practitioners of shamanism. Mescaline content of the cortical stem chlorenchyma of each cactus was determined by Soxhlet extraction with methanol, followed by acid-base extraction with water and dichloromethane, and high-pressure liquid chromatography (HPLC). By virtue of the consistent analytical procedures used, comparable alkaloid concentrations were obtained that facilitated the ranking of the various selected species and cultivars of Echinopsis, all of which exhibited positive mescaline contents. The range of mescaline concentrations across the 14 taxa/cultivars spanned two orders of magnitude, from 0.053% to 4.7% by dry weight. The mescaline concentrations reported here largely support the hypothesis that plants with the highest mescaline concentrations - particularly E. pachanoi from Peru - are most associated with documented shamanic use. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  1. Effects of nanomolar cadmium concentrations on water plants - comparison of biochemical and biophysical mechanisms of toxicity under environmentally relevant conditions

    OpenAIRE

    Andresen, Elisa

    2014-01-01

    In this thesis, the effects of the highly toxic heavy metal cadmium (Cd) on the rootless aquatic model plant Ceratophyllum demersum are investigated on the biochemical and biophysical level. The experiments were carried out using environmentally relevant conditions, i.e. light and temperature followed a sinusoidal cycle, a low biomass to water ratio resembled the situation in oligotrophic lakes and a continuous exchange of the defined nutrient solution ensured that metal uptake into the plant...

  2. Absent biologically relevant associations between serum inhibin B concentrations and characteristics of polycystic ovary syndrome in normogonadotrophic anovulatory infertility

    NARCIS (Netherlands)

    J.S.E. Laven (Joop); B. Imani (Babak); M.J.C. Eijkemans (René); F.H. de Jong (Frank); B.C.J.M. Fauser (Bart)

    2001-01-01

    textabstractBACKGROUND: Dominant follicle selection is disturbed in normogonadotrophic anovulatory infertility [World Health Organization (WHO) 2] and remaining early antral follicles are either healthy or atretic. This study was conducted to investigate whether

  3. Biological effects of tritiated water in low concentration of human lymphocyte chromosome

    International Nuclear Information System (INIS)

    Tanaka, K.; Kamada, N.; Sawaeda, S.

    1992-01-01

    This study was undertaken to investigate the dose-response relationship of tritiated water (HTO) for chromosome aberration in the human lymphocytes, at low dose in vitro exposure ranging from 0.1-1 Gy. The Relative Biological Effectiveness values of HTO with respect to 60 Co gamma ray at a dose rate of 2 cGy/min(15 mCi/ml), at low dose range for the induction of dicentric and centric ring chromosomes were 2.7 in lymphocytes. Also lymphocytes were chronically exposed to HTO for 67 to 80 hrs at different lower dose rates (0.5 and 0.02 cGy/min). There was a 77% decrease in the yields of dicentrics and centric rings, at the dose rate of 0.02cGy/min of HTO, presenting a clear dose rate effect of HTO. The RBE value of HTO relative to 137 Cs gamma ray was 2.0 at the dose rate of 0.02cGy/min(0.15mCi/ml). This suggests that a higher dose rate of HTO exposure has a higher risk and a decrease of RBE value at low dose rate. These results provide useful information for the assessment of health risks in humans specially exposed to low concentration of HTO. (author). 6 refs., 2 figs

  4. Concentrations, input prediction and probabilistic biological risk assessment of polycyclic aromatic hydrocarbons (PAHs) along Gujarat coastline.

    Science.gov (United States)

    Gosai, Haren B; Sachaniya, Bhumi K; Dudhagara, Dushyant R; Rajpara, Rahul K; Dave, Bharti P

    2018-04-01

    A comprehensive investigation was conducted in order to assess the levels of PAHs, their input prediction and potential risks to bacterial abundance and human health along Gujarat coastline. A total of 40 sediment samples were collected at quarterly intervals within a year from two contaminated sites-Alang-Sosiya Shipbreaking Yard (ASSBRY) and Navlakhi Port (NAV), situated at Gulf of Khambhat and Gulf of Kutch, respectively. The concentration of ΣPAHs ranged from 408.00 to 54240.45 ng g -1  dw, indicating heavy pollution of PAHs at both the contaminated sites. Furthermore, isomeric ratios and principal component analysis have revealed that inputs of PAHs at both contaminated sites were mixed-pyrogenic and petrogenic. Pearson co-relation test and regression analysis have disclosed Nap, Acel and Phe as major predictors for bacterial abundance at both contaminated sites. Significantly, cancer risk assessment of the PAHs has been exercised based on incremental lifetime cancer risks. Overall, index of cancer risk of PAHs for ASSBRY and NAV ranged from 4.11 × 10 -6 -2.11 × 10 -5 and 9.08 × 10 -6 -4.50 × 10 -3 indicating higher cancer risk at NAV compared to ASSBRY. The present findings provide baseline information that may help in developing advanced bioremediation and bioleaching strategies to minimize biological risk.

  5. Influence of environmentally relevant concentrations of vinclozolin on quality, DNA integrity, and antioxidant responses of sterlet Acipenser ruthenus spermatozoa.

    Science.gov (United States)

    Gazo, Ievgeniia; Linhartova, Pavla; Shaliutina, Anna; Hulak, Martin

    2013-04-25

    The effects of vinclozolin (VIN), an anti-androgenic fungicide, on quality, oxidative stress, DNA integrity, and ATP level of sterlet (Acipenser ruthenus) spermatozoa were investigated in vitro. Fish spermatozoa were incubated with different concentrations of vinclozolin (0.5, 2, 10, 15, 20 and 50 μg/l) for 2 h. A dose-dependent reduction in spermatozoa motility and velocity was observed at concentrations of 2-50 μg/l. A dramatic increase in DNA fragmentation was recorded at concentrations 10 μg/l and above. After 2 h exposure at higher test concentrations (10-50 μg/l), oxidative stress was apparent, as reflected by significantly higher levels of protein and lipid oxidation and significantly greater superoxide dismutase activity. Intracellular ATP content of spermatozoa decreased with increasing concentrations of VIN. The results demonstrated that VIN can induce reactive oxygen species stress in fish spermatozoa, which could impair the sperm quality, DNA integrity, ATP content, and the antioxidant defense system. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  6. [Relationship among the Oxygen Concentration, Reactive Oxygen Species and the Biological Characteristics of Mouse Bone Marrow Hematopoietic Stem Cells].

    Science.gov (United States)

    Ren, Si-Hua; He, Yu-Xin; Ma, Yi-Ran; Jin, Jing-Chun; Kang, Dan

    2016-02-01

    To investigate the effects of oxygen concentration and reactive oxygen species (ROS) on the biological characteristics of hematopoietic stem cells (HSC) and to analyzed the relationship among the oxygen concentration, ROS and the biological characteristics of mouse HSC through simulation of oxygen environment experienced by PB HSC during transplantation. The detection of reactive oxygen species (ROS), in vitro amplification, directional differentiation (BFU-E, CFU-GM, CFU-Mix), homing of adhesion molecules (CXCR4, CD44, VLA4, VLA5, P-selectin), migration rate, CFU-S of NOD/SCID mice irradiated with sublethal dose were performed to study the effect of oxgen concentration and reactive oxygen species on the biological characteristics of mouse BM-HSC and the relationship among them. The oxygen concentrations lower than normal oxygen concentration (especially hypoxic oxygen environment) could reduce ROS level and amplify more Lin(-) c-kit(+) Sca-1(+) BM HSC, which was more helpful to the growth of various colonies (BFU-E, CFU-GM, CFU-Mix) and to maintain the migratory ability of HSC, thus promoting CFU-S growth significantly after the transplantation of HSC in NOD/SCID mice irradiated by a sublethal dose. BM HSC exposed to oxygen environments of normal, inconstant oxygen level and strenuously thanging of oxygen concentration could result in higher level of ROS, at the same time, the above-mentioned features and functional indicators were relatively lower. The ROS levels of BM HSC in PB HSCT are closely related to the concentrations and stability of oxygen surrounding the cells. High oxygen concentration results in an high level of ROS, which is not helpful to maintain the biological characteristics of BM HSC. Before transplantation and in vitro amplification, the application of antioxidancs and constant oxygen level environments may be beneficial for transplantation of BMMSC.

  7. Bisphenol A induces superfeminization in the ramshorn snail Marisa cornuarietis(Gastropoda: Prosobranchia) at environmentally relevant concentrations.

    Science.gov (United States)

    Oehlmann, Jörg; Schulte-Oehlmann, Ulrike; Bachmann, Jean; Oetken, Matthias; Lutz, Ilka; Kloas, Werner; Ternes, Thomas A

    2006-04-01

    Previous investigations have shown that bisphenol A (BPA) induces a superfeminization syndrome in the freshwater snail Marisa cornuarietis at concentrations as low as 1 microg/L. Superfemales are characterized by the formation of additional female organs, enlarged accessory sex glands, gross malformations of the pallial oviduct, and a stimulation of egg and clutch production, resulting in increased female mortality. However, these studies were challenged on the basis of incomplete experimentation. Therefore, the objective of the current approach was to bridge several gaps in knowledge by conducting additional experiments. In an initial series of experiments, study results from the reproductive phase of the snails were evaluated in the sub-micrograms per liter range. Before and after the spawning season, superfemale responses were observed [NOEC (no observed effect concentration) 7.9 ng/L, EC10 (effective concentration at 10%) 13.9 ng/L], which were absent during the spawning season. A further experiment investigated the temperature dependence of BPA responses by exposing snails at two temperatures in parallel. The adverse effect of BPA was at least partially masked at 27 degrees C (EC10 998 ng/L) when compared with 20 degrees C (EC10 14.8 ng/L). In M. cornuarietis, BPA acts as an estrogen receptor (ER) agonist, because effects were completely antagonized by a co-exposure to tamoxifen and Faslodex. Antiandrogenic effects of BPA, such as a significant decrease in penis length at 20 degrees C, were also observed. Competitive receptor displacement experiments indicate the presence of androgen- and estrogen-specific binding sites. The affinity for BPA of the estrogen binding sites in M. cornuarietis is higher than that of the ER in aquatic vertebrates. The results emphasize that prosobranchs are affected by BPA at lower concentrations than are other wildlife groups, and the findings also highlight the importance of exposure conditions.

  8. Prediction of Adsorption Equilibrium of VOCs onto Hyper-Cross-Linked Polymeric Resin at Environmentally Relevant Temperatures and Concentrations Using Inverse Gas Chromatography.

    Science.gov (United States)

    Jia, Lijuan; Ma, Jiakai; Shi, Qiuyi; Long, Chao

    2017-01-03

    Hyper-cross-linked polymeric resin (HPR) represents a class of predominantly microporous adsorbents and has good adsorption performance toward VOCs. However, adsorption equilibrium of VOCs onto HPR are limited. In this research, a novel method for predicting adsorption capacities of VOCs on HPR at environmentally relevant temperatures and concentrations using inverse gas chromatography data was proposed. Adsorption equilibrium of six VOCs (n-pentane, n-hexane, dichloromethane, acetone, benzene, 1, 2-dichloroethane) onto HPR in the temperature range of 403-443 K were measured by inverse gas chromatography (IGC). Adsorption capacities at environmentally relevant temperatures (293-328 K) and concentrations (P/P s = 0.1-0.7) were predicted using Dubinin-Radushkevich (DR) equation based on Polany's theory. Taking consideration of the swelling properties of HPR, the volume swelling ratio (r) was introduced and r·V micro was used instead of V micro determined by N 2 adsorption data at 77 K as the parameter q 0 (limiting micropore volume) of the DR equation. The results showed that the adsorption capacities of VOCs at environmentally relevant temperatures and concentrations can be predicted effectively using IGC data, the root-mean-square errors between the predicted and experimental data was below 9.63%. The results are meaningful because they allow accurate prediction of adsorption capacities of adsorbents more quickly and conveniently using IGC data.

  9. The practicalities and pitfalls of establishing a policy-relevant and cost-effective soil biological monitoring scheme

    NARCIS (Netherlands)

    Faber, J.H.; Creamer, R.E.; Mulder, C.; Römbke, J.; Rutgers, M.; Sousa, J.P.; Stone, D.; Griffiths, B.S.

    2013-01-01

    A large number of biological indicators have been proposed over the years for assessing soil quality. Although many of those have been applied in monitoring schemes across Europe, no consensus exists on the extent to which these indicators might perform best and how monitoring schemes can be further

  10. Development of biological treatment of high concentration sodium nitrate waste liquid

    International Nuclear Information System (INIS)

    Ogawa, Naoki; Kuroda, Kazuhiko; Shibata, Katsushi; Kawato, Yoshimi; Meguro, Yoshihiro; Takahashi, Kuniaki

    2009-01-01

    An electrolytic reduction, chemical reduction, and biological reduction have been picked up as a method of nitrate liquid waste treatment system exhausted from the reprocessing process. As a result of comparing them, it was shown that the biological treatment was the most excellent method in safety and the economy. (author)

  11. Concentrations and biological availability of 238U and 230Th in the environs of a uranium milling operation

    International Nuclear Information System (INIS)

    Ibrahim, S.; Flot, S.; Whicker, F.W.

    1982-01-01

    This paper reports on a study whose objectives were to determine 238 U and 230 Th concentrations in soil and native plants from various sites around a conventional acid leach uranium milling operation in the Western US, and to estimate plant/soil concentration factors. Soil and vegetation samples were collected from exposed, weathered tailings; near the edge of a tailings pond; from a reclamation area; and at several native range background (control) locations. The results indicate that mean plant/soil concentration factors varied significantly among sites and between radionuclides, but no significant differences between plant groups were found. Concentration factors for 230 Th were greater than for 238 U for plants growing at the edge of the tailings pond. It is speculated that the lower concentration factors for uranium relative to thorium at this site may be due to the proportion of their contents in soil that is biologically available for plant uptake

  12. Elements determination of clinical relevance in biological tissues Dmd{sup mdx}/J dystrophic mice strains investigated by NAA; Determinacao de elementos de relevancia clinica em tecidos biologicos de camundongos distroficos Dmd{sup mdx}/J por AAN

    Energy Technology Data Exchange (ETDEWEB)

    Metairon, Sabrina

    2012-07-01

    In this work the determination of chemistry elements in biological tissues (whole blood, bones and organs) of dystrophic mice, used as animal model of Duchenne Muscular Dystrophy (DMD), was performed using analytical nuclear technique. The aim of this work was to determine reference values of elements of clinical (Ca, Cl, K, Mg, Na) and nutritional (Br and S) relevance in whole blood, tibia, quadriceps and hearts from Dmdmdx/J (10 males and 10 females) dystrophic mice and C57BL/6J (10 males) control group mice, using Neutron Activation Analysis technique (NAA). To show in more details the alterations that this disease may cause in these biological tissues, correlations matrixes of the DMD{sup mdx}/J mouse strain were generated and compared with C57BL/6J control group. For this study 119 samples of biological tissue were irradiated in the IEA-R1 nuclear reactor at IPEN (Sao Paulo, Brazil). The concentrations of these elements in biological tissues of Dmd{sup mdx}/J and C57B/6J mice are the first indicative interval for reference values. Moreover, the alteration in some correlation coefficients data among the elements in the health status and in the diseased status indicates a connection between these elements in whole blood, tibia, quadriceps and heart. These results may help the researchers to evaluate the efficiency of new treatments and to compare the advantages of different treatment approaches before performing tests in patients with muscular dystrophy. (author)

  13. Effects of Field-Relevant Concentrations of Clothianidin on Larval Development of the Butterfly Polyommatus icarus (Lepidoptera, Lycaenidae).

    Science.gov (United States)

    Basley, Kate; Goulson, Dave

    2018-04-03

    Arable field margins are often sown with wildflowers to encourage pollinators and other beneficial or desirable insects such as bees and butterflies. Concern has been raised that these margins may be contaminated with systemic pesticides such as neonicotinoids used on the adjacent crop, and that this may negatively impact beneficial insects. The use of neonicotinoids has been linked to butterfly declines, and species such as the common blue butterfly ( Polyommatus icarus) that feed upon legumes commonly sown in arable field margins, may be exposed to such toxins. Here, we demonstrate that the larval food plants of P. icarus growing in an arable field margin adjacent to a wheat crop treated with the neonicotinoid clothianidin not only contain the pesticide at concentrations comparable to and sometimes higher than those found in foliage of treated crops (range 0.2-48 ppb) but also remain detectable at these levels for up to 21 months after sowing of the crop. Overall, our study demonstrates that nontarget herbivorous organisms in arable field margins are likely to be chronically exposed to neonicotinoids. Under laboratory conditions, exposure to clothianidin at 15 ppb (a field-realistic dose) or above reduced larval growth for the first 9 days of the experiment. Although there was evidence of clothianidin inducing mortality in larvae, with highest survival in control groups, the dose-response relationship was unclear. Our study suggests that larvae of this butterfly exhibit some deleterious sublethal and sometimes lethal impacts of exposure to clothianidin, but many larvae survive to adulthood even when exposed to high doses.

  14. Integrated DNA methylation and copy-number profiling identify three clinically and biologically relevant groups of anaplastic glioma.

    Science.gov (United States)

    Wiestler, Benedikt; Capper, David; Sill, Martin; Jones, David T W; Hovestadt, Volker; Sturm, Dominik; Koelsche, Christian; Bertoni, Anna; Schweizer, Leonille; Korshunov, Andrey; Weiß, Elisa K; Schliesser, Maximilian G; Radbruch, Alexander; Herold-Mende, Christel; Roth, Patrick; Unterberg, Andreas; Hartmann, Christian; Pietsch, Torsten; Reifenberger, Guido; Lichter, Peter; Radlwimmer, Bernhard; Platten, Michael; Pfister, Stefan M; von Deimling, Andreas; Weller, Michael; Wick, Wolfgang

    2014-10-01

    The outcome of patients with anaplastic gliomas varies considerably. Whether a molecular classification of anaplastic gliomas based on large-scale genomic or epigenomic analyses is superior to histopathology for reflecting distinct biological groups, predicting outcomes and guiding therapy decisions has yet to be determined. Epigenome-wide DNA methylation analysis, using a platform which also allows the detection of copy-number aberrations, was performed in a cohort of 228 patients with anaplastic gliomas (astrocytomas, oligoastrocytomas, and oligodendrogliomas), including 115 patients of the NOA-04 trial. We further compared these tumors with a group of 55 glioblastomas. Unsupervised clustering of DNA methylation patterns revealed two main groups correlated with IDH status: CpG island methylator phenotype (CIMP) positive (77.5 %) or negative (22.5 %). CIMP(pos) (IDH mutant) tumors showed a further separation based on copy-number status of chromosome arms 1p and 19q. CIMP(neg) (IDH wild type) tumors showed hallmark copy-number alterations of glioblastomas, and clustered together with CIMP(neg) glioblastomas without forming separate groups based on WHO grade. Notably, there was no molecular evidence for a distinct biological entity representing anaplastic oligoastrocytoma. Tumor classification based on CIMP and 1p/19q status was significantly associated with survival, allowing a better prediction of outcome than the current histopathological classification: patients with CIMP(pos) tumors with 1p/19q codeletion (CIMP-codel) had the best prognosis, followed by patients with CIMP(pos) tumors but intact 1p/19q status (CIMP-non-codel). Patients with CIMP(neg) anaplastic gliomas (GBM-like) had the worst prognosis. Collectively, our data suggest that anaplastic gliomas can be grouped by IDH and 1p/19q status into three molecular groups that show clear links to underlying biology and a significant association with clinical outcome in a prospective trial cohort.

  15. Salt-stimulation of caesium accumulation in the euryhaline green microalga Chlorella salina: potential relevance to the development of a biological Cs-removal process

    Energy Technology Data Exchange (ETDEWEB)

    Avery, S. V.; Codd, G. A.; Gadd, G. M. [Department of Biological Sciences, University of Dundee, Dundee DD1 4HN (United Kingdom)

    1993-07-01

    Accumulation of Cs{sup +} by Chlorella salina was 28-fold greater in cells incubated in the presence than in the absence of 0.5 M-NaCl. An approximate 70% removal of external Cs{sup +} resulted after 15 h incubation of cells with 50 μ;M-CsCl and 0.5 M-NaCl. LiCl also had a stimulatory effect on Cs{sup +} uptake, although mannitol did not. Cs{sup +} influx increased with increasing external NaCl concentration and was maximal between 25-500 mM-NaCl at approximately 4 nmol Cs{sup +} h−1 (10{sup 6} cells){sup −1}. Little effect on Cs{sup +} uptake resulted from the presence of Mg{sup 2+} or Ca{sup 2+} or from varying the external pH, and Cs{sup +} was relatively non-toxic towards C. salina. At increasing cell densities (from 4 × 10{sup 5} to 1 × 10{sup 7} cells ml{sup +1}), decreasing amounts of Cs{sup +} were accumulated per cell although the rate of Cs{sup +} removal from the external medium was still greatest at the higher cell densities examined. Freely suspended C. salina and cell-loaded alginate microbeads accumulated similar levels of Cs{sup +}, however, 46% of total Cs{sup +} uptake was attributable to the calcium-alginate matrix in the latter case. When Cs{sup +}-loaded cells were subjected to hypoosmotic shock, loss of cellular Cs{sup +} occurred allowing easy Cs{sup +} recovery. This loss exceeded 90% of cellular Cs{sup +} when cells were washed with solutions containing ≤ 50 mM-NaCl between consecutive Cs{sup +} uptake periods; these cells subsequently lost their ability to accumulate large amounts of Cs{sup +}. Maximal Cs{sup +} uptake (approximately 85.1% removal after three 15 h incubations) occurred when cells were washed with a solution containing 500 mM-NaCl and 200 mM-KCl between incubations. The relevance of these results to the possible use of C. salina in a salt-dependent biological Cs-removal process is discussed. (author)

  16. Environmentally-relevant concentrations of atrazine induce non-monotonic acceleration of developmental rate and increased size at metamorphosis in Rhinella arenarum tadpoles.

    Science.gov (United States)

    Brodeur, Julie C; Sassone, Alina; Hermida, Gladys N; Codugnello, Nadia

    2013-06-01

    Despite of the various studies reporting on the subject, anticipating the impacts of the widely-used herbicide atrazine on anuran tadpoles metamorphosis remains complex as increases or decreases of larval period duration are almost as frequently reported as an absence of effect. The aim of the present study was to examine the effects of environmentally-relevant concentrations of atrazine (0.1, 1, 10, 100, and 1000μg/L) on the timings of metamorphosis and body size at metamorphosis in the common South American toad, Rhinella arenarum (Anura: bufonidae). None of the atrazine concentrations tested significantly altered survival. Low atrazine concentrations in the range of 1-100μg/L were found to accelerate developmental rate in a non-monotonic U-shaped concentration-response relationship. This observed acceleration of the metamorphic process occurred entirely between stages 25 and 39; treated tadpoles proceeding through metamorphosis as control animals beyond this point. Together with proceeding through metamorphosis at a faster rate, tadpoles exposed to atrazine concentrations in the range of 1-100μg/L furthermore transformed into significantly larger metamorphs than controls, the concentration-response curve taking the form of an inverted U in this case. The no observed effect concentration (NOEC) was 0.1μg atrazine/L for both size at metamorphosis and timings of metamorphosis. Tadpoles exposed to 100μg/L 17β-estradiol presented the exact same alterations of developmental rate and body size as those treated with 1, 10 and 100μg/L of atrazine. Elements of the experimental design that facilitated the detection of alterations of metamorphosis at low concentrations of atrazine are discussed, together with the ecological significance of those findings. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Toxicity of TiO2 nanoparticles on soil nitrification at environmentally relevant concentrations: Lack of classical dose-response relationships.

    Science.gov (United States)

    Simonin, Marie; Martins, Jean M F; Le Roux, Xavier; Uzu, Gaëlle; Calas, Aude; Richaume, Agnès

    2017-03-01

    Titanium-dioxide nanoparticles (TiO 2 -NPs) are increasingly released in agricultural soils through, e.g. biosolids, irrigation or nanoagrochemicals. Soils are submitted to a wide range of concentrations of TiO 2 -NPs depending on the type of exposure. However, most studies have assessed the effects of unrealistically high concentrations, and the dose-response relationships are not well characterized for soil microbial communities. Here, using soil microcosms, we assessed the impact of TiO 2 -NPs at concentrations ranging from 0.05 to 500 mg kg -1  dry-soil, on the activity and abundance of ammonia-oxidizing archaea (AOA) and bacteria (AOB), and nitrite-oxidizing bacteria (Nitrobacter and Nitrospira). In addition, aggregation and oxidative potential of TiO 2 -NPs were measured in the spiking suspensions, as they can be important drivers of TiO 2 -NPs toxicity. After 90 days of exposure, non-classical dose-response relationships were observed for nitrifier abundance or activity, making threshold concentrations impossible to compute. Indeed, AOA abundance was reduced by 40% by TiO 2 -NPs whatever the concentration, while Nitrospira was never affected. Moreover, AOB and Nitrobacter abundances were decreased mainly at intermediate concentrations nitrification was reduced by 25% at the lowest (0.05 mg kg -1 ) and the highest (100 and 500 mg kg -1 ) TiO 2 -NPs concentrations. Path analyses indicated that TiO 2 -NPs affected nitrification through an effect on the specific activity of nitrifiers, in addition to indirect effects on nitrifier abundances. Altogether these results point out the need to include very low concentrations of NPs in soil toxicological studies, and the lack of relevance of classical dose-response tests and ecotoxicological dose metrics (EC50, IC50…) for TiO 2 -NPs impact on soil microorganisms.

  18. SysBioCube: A Data Warehouse and Integrative Data Analysis Platform Facilitating Systems Biology Studies of Disorders of Military Relevance.

    Science.gov (United States)

    Chowbina, Sudhir; Hammamieh, Rasha; Kumar, Raina; Chakraborty, Nabarun; Yang, Ruoting; Mudunuri, Uma; Jett, Marti; Palma, Joseph M; Stephens, Robert

    2013-01-01

    SysBioCube is an integrated data warehouse and analysis platform for experimental data relating to diseases of military relevance developed for the US Army Medical Research and Materiel Command Systems Biology Enterprise (SBE). It brings together, under a single database environment, pathophysio-, psychological, molecular and biochemical data from mouse models of post-traumatic stress disorder and (pre-) clinical data from human PTSD patients.. SysBioCube will organize, centralize and normalize this data and provide an access portal for subsequent analysis to the SBE. It provides new or expanded browsing, querying and visualization to provide better understanding of the systems biology of PTSD, all brought about through the integrated environment. We employ Oracle database technology to store the data using an integrated hierarchical database schema design. The web interface provides researchers with systematic information and option to interrogate the profiles of pan-omics component across different data types, experimental designs and other covariates.

  19. Convergence of regenerative medicine and synthetic biology to develop standardized and validated models of human diseases with clinical relevance.

    Science.gov (United States)

    Hutmacher, Dietmar Werner; Holzapfel, Boris Michael; De-Juan-Pardo, Elena Maria; Pereira, Brooke Anne; Ellem, Stuart John; Loessner, Daniela; Risbridger, Gail Petuna

    2015-12-01

    In order to progress beyond currently available medical devices and implants, the concept of tissue engineering has moved into the centre of biomedical research worldwide. The aim of this approach is not to replace damaged tissue with an implant or device but rather to prompt the patient's own tissue to enact a regenerative response by using a tissue-engineered construct to assemble new functional and healthy tissue. More recently, it has been suggested that the combination of Synthetic Biology and translational tissue-engineering techniques could enhance the field of personalized medicine, not only from a regenerative medicine perspective, but also to provide frontier technologies for building and transforming the research landscape in the field of in vitro and in vivo disease models. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  20. Biological responses of two marine organisms of ecological relevance to on-going ocean acidification and global warming.

    Science.gov (United States)

    Gomiero, A; Bellerby, R G J; Manca Zeichen, M; Babbini, L; Viarengo, A

    2018-05-01

    Recently, there has been a growing concern that climate change may rapidly and extensively alter global ecosystems with unknown consequences for terrestrial and aquatic life. While considerable emphasis has been placed on terrestrial ecology consequences, aquatic environments have received relatively little attention. Limited knowledge is available on the biological effects of increments of seawater temperature and pH decrements on key ecological species, i.e., primary producers and/or organisms representative of the basis of the trophic web. In the present study, we addressed the biological effects of global warming and ocean acidification on two model organisms, the microbenthic marine ciliate Euplotes crassus and the green alga Dunaliella tertiocleta using a suite of high level ecological endpoint tests and sub-lethal stress measures. Organisms were exposed to combinations of pH and temperature (TR1: 7.9 [pH], 25.5 °C and TR2: 7.8 [pH], 27,0 °C) simulating two possible environmental scenarios predicted to occur in the habitats of the selected species before the end of this century. The outcomes of the present study showed that the tested scenarios did not induce a significant increment of mortality on protozoa. Under the most severe exposure conditions, sub-lethal stress indices show that pH homeostatic mechanisms have energetic costs that divert energy from essential cellular processes and functions. The marine protozoan exhibited significant impairment of the lysosomal compartment and early signs of oxidative stress under these conditions. Similarly, significant impairment of photosynthetic efficiency and an increment in lipid peroxidation were observed in the autotroph model organism held under the most extreme exposure condition tested. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Effect of high calcium concentration influents on enhanced biological phosphorus removal process

    International Nuclear Information System (INIS)

    Montoya Martinez, T.; Aguado Garcia, D.; Ferrer Polo, J.

    2010-01-01

    In this work, the effect of calcium concentration in wastewater on the polyphosphate accumulating organisms (PAO) is investigated as well as its influence in PAO metabolism, specifically in the Y P O4 (ratio between phosphorus release and acetic acid uptake). For this study a sequencing batch reactor (SBR) anaerobic-aerobic was used, in which the PAO enriched biomass was exposed to different calcium concentrations in the influent wastewater. The results indicate that until a given calcium level in the influent wastewater (35 mg Ca/l) the metabolism is not affect, but higher calcium concentrations lead to significant Y P O4 decline. (Author) 18 refs.

  2. Biological Production of a Hydrocarbon Fuel Intermediate Polyhydroxybutyrate (PHB) from a Process Relevant Lignocellulosic Derived Sugar (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Wang, W.; Mittal, A.; Mohagheghi, A.; Johnson, D. K.

    2014-04-01

    PHAs are synthesized by many microorganisms to serve as intracellular carbon storage molecules. In some bacterial strains, PHB can account for up to 80% of cell mass. In addition to its application in the packaging sector, PHB also has great potential as an intermediate in the production of hydrocarbon fuels. PHB can be thermally depolymerized and decarboxylated to propene which can be upgraded to hydrocarbon fuels via commercial oligomerization technologies. Cupriavidus necator is the microorganism that has been most extensively studied and used for PHB production on an industrial scale; However the substrates used for producing PHB are mainly fructose, glucose, sucrose, fatty acids, glycerol, etc., which are expensive. In this study, we demonstrate production of PHB from a process relevant lignocellulosic derived sugar stream, i.e., saccharified slurry from pretreated corn stover. The strain was first investigated in shake flasks for its ability to utilize glucose, xylose and acetate. In addition, the strain was also grown on pretreated lignocellulose hydrolyzate slurry and evaluated in terms of cell growth, sugar utilization, PHB accumulation, etc. The mechanism of inhibition in the toxic hydrolysate generated by the pretreatment and saccharification process of biomass, was also studied.

  3. Set-up and calibration of a method to measure {sup 10}B concentration in biological samples by neutron autoradiography

    Energy Technology Data Exchange (ETDEWEB)

    Gadan, M.A. [National Commission for Atomic Energy (CNEA), Buenos Aires (Argentina); Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); Bortolussi, S., E-mail: silva.bortolussi@pv.infn.it [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); National Institute for Nuclear Physics (INFN), Section of Pavia, Pavia (Italy); Postuma, I. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); Ballarini, F. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); National Institute for Nuclear Physics (INFN), Section of Pavia, Pavia (Italy); Bruschi, P. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); Protti, N.; Santoro, D.; Stella, S. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); National Institute for Nuclear Physics (INFN), Section of Pavia, Pavia (Italy); Cansolino, L.; Clerici, A.; Ferrari, C.; Zonta, A.; Zonta, C. [Department of Experimental Surgery, University of Pavia, Pavia (Italy); Altieri, S. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); National Institute for Nuclear Physics (INFN), Section of Pavia, Pavia (Italy)

    2012-03-01

    A selective uptake of boron in the tumor is the base of Boron Neutron Capture Therapy, which can destroy the tumor substantially sparing the normal tissue. In order to deliver a lethal dose to the tumor, keeping the dose absorbed by normal tissues below the tolerance level, it is mandatory to know the {sup 10}B concentration present in each kind of tissue at the moment of irradiation. This work presents the calibration procedure adopted for a boron concentration measurement method based on neutron autoradiography, where biological samples are deposited on sensitive films and irradiated in the thermal column of the TRIGA reactor (University of Pavia). The latent tracks produced in the film by the charged particles coming from the neutron capture in {sup 10}B are made visible by a proper etching, allowing the measurement of the track density. A calibration procedure with standard samples provides curves of track density as a function of boron concentration, to be used in the measurement of biological samples. In this paper, the bulk etch rate parameter and the calibration curves obtained for both liquid samples and biological tissues with known boron concentration are presented. A bulk etch rate value of (1.64 {+-} 0.02) {mu}m/h and a linear dependence with etching time were found. The plots representing the track density versus the boron concentration in a range between 5 and 50 {mu}g/g (ppm) are linear, with an angular coefficient of (1.614 {+-} 0.169){center_dot}10{sup -3} tracks/({mu}m{sup 2} ppm) for liquids and (1.598 {+-} 0.097){center_dot}10{sup -2} tracks/({mu}m{sup 2} ppm) for tissues.

  4. Why we should use simpler models if the data allow this: relevance for ANOVA designs in experimental biology

    Directory of Open Access Journals (Sweden)

    Lazic Stanley E

    2008-07-01

    Full Text Available Abstract Background Analysis of variance (ANOVA is a common statistical technique in physiological research, and often one or more of the independent/predictor variables such as dose, time, or age, can be treated as a continuous, rather than a categorical variable during analysis – even if subjects were randomly assigned to treatment groups. While this is not common, there are a number of advantages of such an approach, including greater statistical power due to increased precision, a simpler and more informative interpretation of the results, greater parsimony, and transformation of the predictor variable is possible. Results An example is given from an experiment where rats were randomly assigned to receive either 0, 60, 180, or 240 mg/L of fluoxetine in their drinking water, with performance on the forced swim test as the outcome measure. Dose was treated as either a categorical or continuous variable during analysis, with the latter analysis leading to a more powerful test (p = 0.021 vs. p = 0.159. This will be true in general, and the reasons for this are discussed. Conclusion There are many advantages to treating variables as continuous numeric variables if the data allow this, and this should be employed more often in experimental biology. Failure to use the optimal analysis runs the risk of missing significant effects or relationships.

  5. Identification of Genes Relevant to Pesticides and Biology from Global Transcriptome Data of Monochamus alternatus Hope (Coleoptera: Cerambycidae Larvae.

    Directory of Open Access Journals (Sweden)

    Songqing Wu

    Full Text Available Monochamus alternatus Hope is the main vector in China of the Pine Wilt Disease caused by the pine wood nematode Bursaphelenchus xylophilus. Although chemical control is traditionally used to prevent pine wilt disease, new strategies based in biological control are promising ways for the management of the disease. However, there is no deep sequence analysis of Monochamus alternatus Hope that describes the transcriptome and no information is available about gene function of this insect vector. We used next generation sequencing technology to sequence the whole fourth instar larva transcriptome of Monochamus alternatus Hope and successfully built a Monochamus alternatus Hope transcriptome database. In total, 105,612 unigenes were assigned for Gene Ontology (GO terms, information for 16,730 classified unigenes was obtained in the Clusters of Orthologous Groups (COGs database, and 13,024 unigenes matched with 224 predicted pathways in the Kyoto Encyclopedia of Genes and Genome (KEGG. In addition, genes related to putative insecticide resistance-related genes, RNAi, the Bt receptor, intestinal digestive enzymes, possible future insect control targets and immune-related molecules are described. This study provides valuable basic information that can be used as a gateway to develop new molecular tools for Monochamus alternatus Hope control strategies.

  6. Method for the concentration and separation of actinides from biological and environmental samples

    International Nuclear Information System (INIS)

    Horwitz, E.P.; Dietz, M.L.

    1989-01-01

    A method and apparatus for the quantitative recover of actinide values from biological and environmental sample by passing appropriately prepared samples in a mineral acid solution through a separation column of a dialkyl(phenyl)-N,N-dialylcarbamoylmethylphosphine oxide dissolved in tri-n-butyl phosphate on an inert substrate which selectively extracts the actinide values. The actinide values can be eluted either as a group or individually and their presence quantitatively detected by alpha counting. 3 figs

  7. Determination of element concentrations in biological reference materials by solid sampling and other analytical methods

    International Nuclear Information System (INIS)

    Schauenburg, H.; Weigert, P.

    1992-01-01

    Using solid sampling with graphite furnace atomic absorption spectrometry (GFAAS), values for cadmium, copper, lead and zinc in six biological reference materials were obtained from up to four laboratories participating in three collaborative studies. These results are compared with those obtained with other methods used in routine analysis from laboratories of official food control. Under certain conditions solid sampling with GFAAS seems to be suitable for routine analysis as well as conventional methods. (orig.)

  8. Compromising σ-1 receptors at the endoplasmic reticulum render cytotoxicity to physiologically relevant concentrations of dopamine in a nuclear factor-κB/Bcl-2-dependent mechanism: potential relevance to Parkinson's disease.

    Science.gov (United States)

    Mori, Tomohisa; Hayashi, Teruo; Su, Tsung-Ping

    2012-06-01

    The endoplasmic reticulum (ER) chaperone σ-1 receptor (Sig-1R) is cytoprotective against ER stress-induced apoptosis. The level of Sig-1Rs in the brain was reported to be lower in early parkinsonian patients. Because dopamine (DA) toxicity is well known to be involved in the etiology of Parkinson's disease, we tested in this study whether a relationship might exist between Sig-1Rs and DA-induced cytotoxicity in a cellular model by using Chinese hamster ovary (CHO) cells. DA in physiological concentrations (e.g., lower than 10 μM) does not cause apoptosis. However, the same concentrations of DA cause apoptosis in Sig-1R knockdown CHO cells. In search of a mechanistic explanation, we found that unfolded protein response is not involved. Rather, the level of protective protein Bcl-2 is critically involved in this DA/Sig-1R knockdown-induced apoptosis. Specifically, the DA/Sig-1R knockdown causes a synergistic proteasomal conversion of nuclear factor κB (NF-κB) p105 to the active form of p50, which is known to down-regulate the transcription of Bcl-2. It is noteworthy that the DA/Sig-1R knockdown-induced apoptosis is blocked by the overexpression of Bcl-2. Our results therefore indicate that DA is involved in the activation of NF-κB and suggest that endogenous Sig-1Rs are tonically inhibiting the proteasomal conversion/activation of NF-κB caused by physiologically relevant concentrations of DA that would otherwise cause apoptosis. Thus, Sig-1Rs and associated ligands may represent new therapeutic targets for the treatment of parkinsonism.

  9. Seven-day human biological rhythms: An expedition in search of their origin, synchronization, functional advantage, adaptive value and clinical relevance.

    Science.gov (United States)

    Reinberg, Alain E; Dejardin, Laurence; Smolensky, Michael H; Touitou, Yvan

    2017-01-01

    This fact-finding expedition explores the perspectives and knowledge of the origin and functional relevance of the 7 d domain of the biological time structure, with special reference to human beings. These biological rhythms are displayed at various levels of organization in diverse species - from the unicellular sea algae of Acetabularia and Goniaulax to plants, insects, fish, birds and mammals, including man - under natural as well as artificial, i.e. constant, environmental conditions. Nonetheless, very little is known about their derivation, functional advantage, adaptive value, synchronization and potential clinical relevance. About 7 d cosmic cycles are seemingly too weak, and the 6 d work/1 d rest week commanded from G-d through the Laws of Mosses to the Hebrews is too recent an event to be the origin in humans. Moreover, human and insect studies conducted under controlled constant conditions devoid of environmental, social and other time cues report the persistence of 7 d rhythms, but with a slightly different (free-running) period (τ), indicating their source is endogenous. Yet, a series of human and laboratory rodent studies reveal certain mainly non-cyclic exogenous events can trigger 7 d rhythm-like phenomena. However, it is unknown whether such triggers unmask, amplify and/or synchronize previous non-overtly expressed oscillations. Circadian (~24 h), circa-monthly (~30 d) and circannual (~1 y) rhythms are viewed as genetically based features of life forms that during evolution conferred significant functional advantage to individual organisms and survival value to species. No such advantages are apparent for endogenous 7 d rhythms, raising several questions: What is the significance of the 7 d activity/rest cycle, i.e. week, storied in the Book of Genesis and adopted by the Hebrews and thereafter the residents of nearby Mediterranean countries and ultimately the world? Why do humans require 1 d off per 7 d span? Do 7 d rhythms bestow functional

  10. US Subseabed Disposal Program radioecological data base: summaries of available radionuclide concentration factors and biological half-lives

    International Nuclear Information System (INIS)

    Gomez, L.S.; Marietta, M.G.; Jackson, D.W.

    1984-01-01

    The US Subseabed Disposal Program has compiled an extensive objective concentration factor and biological half-life data base from the international marine radioecological literature. A microcomputer-based data management system has been implemented to provide statistical and graphical summaries of these data. The data base is constructed in a manner which allows subsets to be sorted using a number of inter-study variables such as organism category, tissue/organ category, geographic location (for in situ studies), and several laboratory-related conditions (e.g., exposure time and exposure concentration). We discuss concentration factor data summaries for many elements. We also discuss summary material for biological half-life data. We discuss the results of our review with the estimates of mean concentration factors provided by the IAEA. It is proposed that this presentation scheme will enable those concerned with predictive assessment of radiation dose in the marine environment to make a more judicious selection of data for a given application. 7 references

  11. Evaluation of the biological effect of the concentration of ''CMU''on the leaves plant breeding

    International Nuclear Information System (INIS)

    Revilla Pedreira, R.

    1980-01-01

    The effect of CMU (3-p-chlorophenyl)-1,1-dimethylurea on the photosynthetic activity of six species of higher plants and on chlorella pyrenoidosa was studied. In the higher plants the absorption of CMU was studied using 14 C-CMU. The effect of different concentrations of this herbicide on the photosynthetic assimilation of CO 2 by the plant's leaves has also been determined. Moreover, the inhibitory effect of the CMU on the Hill reaction of isolated chloroplasts has been studied. The results indicate that there is a correlation between the concentration of the herbicide and the degree of inhibition of photosynthesis for concentration between 10 -8 M and 10 -4 M. As a consequence of the results obtained, a biotest is proposed for the detection of residues of the photosynthesis inhibitors using the alga chlorella pyrenoidosa as the sensory element. (auth.)

  12. Simulation to aid in interpreting biological relevance and setting of population-level protection goals for risk assessment of pesticides.

    Science.gov (United States)

    Topping, Christopher John; Luttik, Robert

    2017-10-01

    Specific protection goals (SPGs) comprise an explicit expression of the environmental components that need protection and the maximum impacts that can be tolerated. SPGs are set by risk managers and are typically based on protecting populations or functions. However, the measurable endpoints available to risk managers, at least for vertebrates, are typically laboratory tests. We demonstrate, using the example of eggshell thinning in skylarks, how simulation can be used to place laboratory endpoints in context of population-level effects as an aid to setting the SPGs. We develop explanatory scenarios investigating the impact of different assumptions of eggshell thinning on skylark population size, density and distribution in 10 Danish landscapes, chosen to represent the range of typical Danish agricultural conditions. Landscape and timing of application of the pesticide were found to be the most critical factors to consider in the impact assessment. Consequently, a regulatory scenario of monoculture spring barley with an early spray treatment eliciting the eggshell thinning effect was applied using concentrations eliciting effects of zero to 100% in steps of 5%. Setting the SPGs requires balancing scientific, social and political realities. However, the provision of clear and detailed options such as those from comprehensive simulation results can inform the decision process by improving transparency and by putting the more abstract testing data into the context of real-world impacts. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Assessment of a combined gas chromatography mass spectrometer sensor (GC-MSS) system for detecting biologically relevant volatile compounds (VCs).

    Science.gov (United States)

    Gould, Oliver; Wieczorek, Tomas; de Lacy Costello, Ben P J; Persad, Raj; Ratcliffe, Norman

    2017-09-26

    There have been a number of studies in which metal oxide sensors (MOS) have replaced conventional analytical detectors in gas chromatography systems. However, despite the use of these instruments in a range of applications including breath research the sensor responses (i.e. resistance changes w.r.t. concentration of VCs) remain largely unreported. This paper addresses that issue by comparing the response of a metal oxide sensor directly with a mass spectrometer (MS), whereby both detectors are interfaced to the same GC column using an s-swafer. It was demonstrated that the sensitivity of an in-house fabricated ZnO/ SnO2 thick film MOS was superior to a modern MS for the detection of a wide range of volatile compounds (VCs) of different functionalities and masses. Better techniques for detection and quantification of these VCs is valuable, as many of these compounds are commonly reported throughout the scientific literature. This is also the first published report of a combined GC-MS sensor system. These 2 different detector technologies when combined, should enhance discriminatory abilities to aid disease diagnoses using volatiles from e.g. breath, and bodily fluids. 29 chemical standards have been tested using solid phase micro-extraction; 25 of these compounds are found on human breath. In all but 2 instances the sensor exhibited the same or superior limit of detection compared to the MS. 12 stool samples from healthy participants were analysed, the sensor detected, on average 1.6 peaks more per sample than the MS. Similarly analysing the headspace of E. coli broth cultures the sensor detected 6.9 more peaks per sample versus the MS. This greater sensitivity is primarily a function of the superior limits of detection of the metal oxide sensor. This shows that systems based on the combination of chromatography systems with solid state sensors shows promise for a range of applications. © 2017 IOP Publishing Ltd.

  14. A Sensitive Cell-Based Assay to Measure the Doxycycline Concentration in Biological Samples

    NARCIS (Netherlands)

    Kleibeuker, Wendy; Zhou, Xue; Centlivre, Mireille; Legrand, Nicolas; Page, Mark; Almond, Neil; Berkhout, Ben; Das, Atze T.

    2009-01-01

    Doxycycline (DOX) is widely used as a pharmacological agent and as an effector molecule in inducible gene expression systems. For most applications, it is important to determine whether the DOX concentration reaches the level required for optimal efficacy. We developed a sensitive bioassay for

  15. Compilation of elemental concentration data for NBS Biological and Environmental Standard Reference Materials

    International Nuclear Information System (INIS)

    Gladney, E.S.

    1980-07-01

    Concentration data on up to 76 elementals in 19 NBS Standard Reference Materials have been collected from 325 journal articles and technical reports. These data are summarized into mean +- one standard deviation values and compared with available data from NBS and other review articles. Data are presented on the analytical procedures employed and all raw data are presented in appendixes

  16. Biological phosphorus and nitrogen removal in sequencing batch reactors: effects of cycle length, dissolved oxygen concentration and influent particulate matter.

    Science.gov (United States)

    Ginige, Maneesha P; Kayaalp, Ahmet S; Cheng, Ka Yu; Wylie, Jason; Kaksonen, Anna H

    2013-01-01

    Removal of phosphorus (P) and nitrogen (N) from municipal wastewaters is required to mitigate eutrophication of receiving water bodies. While most treatment plants achieve good N removal using influent carbon (C), the use of influent C to facilitate enhanced biological phosphorus removal (EBPR) is poorly explored. A number of operational parameters can facilitate optimum use of influent C and this study investigated the effects of cycle length, dissolved oxygen (DO) concentration during aerobic period and influent solids on biological P and N removal in sequencing batch reactors (SRBs) using municipal wastewaters. Increasing cycle length from 3 to 6 h increased P removal efficiency, which was attributed to larger portion of N being removed via nitrite pathway and more biodegradable organic C becoming available for EBPR. Further increasing cycle length from 6 to 8 h decreased P removal efficiencies as the demand for biodegradable organic C for denitrification increased as a result of complete nitrification. Decreasing DO concentration in the aerobic period from 2 to 0.8 mg L(-1) increased P removal efficiency but decreased nitrification rates possibly due to oxygen limitation. Further, sedimented wastewater was proved to be a better influent stream than non-sedimented wastewater possibility due to the detrimental effect of particulate matter on biological nutrient removal.

  17. Insight into the Local Solvent Environment of Biologically Relevant Iron-nitroysl Systems through Two-Dimensional Infrared Spectroscopy

    Science.gov (United States)

    Brookes, Jennifer Faith

    Iron-nitrosyl systems, particularly in the form of heme proteins, with their iron metal active sites play an important role in biological systems. Heme proteins act as storage, transporters, and receptors for nitric oxide (NO), a signaling molecule that is important in immune, nervous, and cardiovascular systems of mammals. By better understanding the local environment of the active site of NO binding heme proteins we can gain insight into disease in which the NO pathways have been implicated. This is an important step to being able to develop pharmaceuticals targeting NO pathways in humans. Sodium nitroprusside ((SNP, Na2[Fe(CN)5is NO]·2H 2O) investigated as a model system for the active site of nitric oxide binding heme proteins. Using two-dimensional infrared spectroscopy (2D IR) to obtain dephasing dynamics of the nitrosyl stretch (nuNO) in a series of solvents we are able to better understand the local environment of the more complicated metalloproteins. Rigorous line shape analysis is performed by using nonlinear response theory to simulate 2D IR spectra which are then fit to experimental data in an iterative process to extract frequency-frequency correlation functions (FFCFs). The time scales obtained are then correlated to empirical solvent polarity parameters. The analysis of the 2D IR lineshapes reveal that the spectral diffusion timescale of the nuNO in SNP varies from 0.8 -- 4 ps and is negatively correlated with the empirical solvent polarity scales. We continue to investigate NO binding of metalloproteins through 2D IR experiments on nitrophorin 4 (NP4). NP4 is a pH-sensitive NO transporter protein present in the salivary gland of the blood sucking insect Rhodius prolixus which undergoes a pH sensitive structural change between a closed and open conformation allowing for the storage and delivery of NO. The two structures are observed spectroscopically as two distinct pH-dependent nu NO frequencies at ~1904 and ~1917 cm-1. We obtain FFCFs by globally

  18. Inhibition of peroxynitrite-mediated DNA strand cleavage and hydroxyl radical formation by aspirin at pharmacologically relevant concentrations: Implications for cancer intervention

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wei [Division of Biomedical Sciences, Edward Via Virginia College of Osteopathic Medicine, Virginia Tech Corporate Research Center, Blacksburg, VA 24060 (United States); College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310035 (China); Department of Food Science and Technology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Zhu, Hong; Jia, Zhenquan [Division of Biomedical Sciences, Edward Via Virginia College of Osteopathic Medicine, Virginia Tech Corporate Research Center, Blacksburg, VA 24060 (United States); Li, Jianrong [College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310035 (China); Misra, Hara P. [Division of Biomedical Sciences, Edward Via Virginia College of Osteopathic Medicine, Virginia Tech Corporate Research Center, Blacksburg, VA 24060 (United States); Zhou, Kequan, E-mail: kzhou@wayne.edu [Department of Nutrition and Food Science, Wayne State University, Detroit, MI 48202 (United States); Li, Yunbo, E-mail: yli@vcom.vt.edu [Division of Biomedical Sciences, Edward Via Virginia College of Osteopathic Medicine, Virginia Tech Corporate Research Center, Blacksburg, VA 24060 (United States)

    2009-12-04

    Epidemiological studies have suggested that the long-term use of aspirin is associated with a decreased incidence of human malignancies, especially colorectal cancer. Since accumulating evidence indicates that peroxynitrite is critically involved in multistage carcinogenesis, this study was undertaken to investigate the ability of aspirin to inhibit peroxynitrite-mediated DNA damage. Peroxynitrite and its generator 3-morpholinosydnonimine (SIN-1) were used to cause DNA strand breaks in {phi}X-174 plasmid DNA. We demonstrated that the presence of aspirin at concentrations (0.25-2 mM) compatible with amounts in plasma during chronic anti-inflammatory therapy resulted in a significant inhibition of DNA cleavage induced by both peroxynitrite and SIN-1. Moreover, the consumption of oxygen caused by 250 {mu}M SIN-1 was found to be decreased in the presence of aspirin, indicating that aspirin might affect the auto-oxidation of SIN-1. Furthermore, EPR spectroscopy using 5,5-dimethylpyrroline-N-oxide (DMPO) as a spin trap demonstrated the formation of DMPO-hydroxyl radical adduct (DMPO-OH) from authentic peroxynitrite, and that aspirin at 0.25-2 mM potently diminished the radical adduct formation in a concentration-dependent manner. Taken together, these results demonstrate for the first time that aspirin at pharmacologically relevant concentrations can inhibit peroxynitrite-mediated DNA strand breakage and hydroxyl radical formation. These results may have implications for cancer intervention by aspirin.

  19. Inhibition of peroxynitrite-mediated DNA strand cleavage and hydroxyl radical formation by aspirin at pharmacologically relevant concentrations: Implications for cancer intervention

    International Nuclear Information System (INIS)

    Chen, Wei; Zhu, Hong; Jia, Zhenquan; Li, Jianrong; Misra, Hara P.; Zhou, Kequan; Li, Yunbo

    2009-01-01

    Epidemiological studies have suggested that the long-term use of aspirin is associated with a decreased incidence of human malignancies, especially colorectal cancer. Since accumulating evidence indicates that peroxynitrite is critically involved in multistage carcinogenesis, this study was undertaken to investigate the ability of aspirin to inhibit peroxynitrite-mediated DNA damage. Peroxynitrite and its generator 3-morpholinosydnonimine (SIN-1) were used to cause DNA strand breaks in φX-174 plasmid DNA. We demonstrated that the presence of aspirin at concentrations (0.25-2 mM) compatible with amounts in plasma during chronic anti-inflammatory therapy resulted in a significant inhibition of DNA cleavage induced by both peroxynitrite and SIN-1. Moreover, the consumption of oxygen caused by 250 μM SIN-1 was found to be decreased in the presence of aspirin, indicating that aspirin might affect the auto-oxidation of SIN-1. Furthermore, EPR spectroscopy using 5,5-dimethylpyrroline-N-oxide (DMPO) as a spin trap demonstrated the formation of DMPO-hydroxyl radical adduct (DMPO-OH) from authentic peroxynitrite, and that aspirin at 0.25-2 mM potently diminished the radical adduct formation in a concentration-dependent manner. Taken together, these results demonstrate for the first time that aspirin at pharmacologically relevant concentrations can inhibit peroxynitrite-mediated DNA strand breakage and hydroxyl radical formation. These results may have implications for cancer intervention by aspirin.

  20. A single exposure of sediment sulphate-reducing bacteria to oxytetracycline concentrations relevant to aquaculture enduringly disturbed their activity, abundance and community structure.

    Science.gov (United States)

    Fernández, M L; Granados-Chinchilla, F; Rodríguez, C

    2015-08-01

    Although feed medicated with antibiotics is widely used in animal production to prevent and treat bacterial infections, the effect of these drugs on nontarget anaerobic bacteria is unknown. We aimed to clarify whether a single exposure of sulphate-reducing bacteria (SRB) from a tilapia pond to oxytetracycline (OTC) concentrations relevant to aquaculture impacts their function, abundance and community structure. To demonstrate changes in SO4(2-) content, SRB abundance, dsrB copy number and SRB diversity, sediment mesocosms were spiked with 5, 25, 50 and 75 mg OTC kg(-1) and examined for 30 days by means of ion chromatography, qPCR, cultivation and fluorescent in situ hybridization (FISH). On day 3, we measured higher SO4(2-) concentrations (ca. two-fold) and a reduction in dsrB copy numbers of approximately 50% in the treatments compared to the controls. After 30 days, a subtle yet measurable enrichment of bacteria from the order Desulfovibrionales occurred in mesocosms receiving ≥ 50 mg OTC kg(-1), notwithstanding that SRB counts decreased two orders of magnitude. OTC was dynamically and reversibly converted into 4-epioxytetracycline and other related compounds in a dose-dependent manner during the experiment. A single exposure to rather high OTC concentrations triggered functional and structural changes in a SRB community that manifested quickly and persisted for a month. This study improves our limited knowledge on the ecotoxicology of antibiotics in anaerobic environments. © 2015 The Society for Applied Microbiology.

  1. The importance of biological factors affecting trace metal concentration as revealed from accumulation patterns in co-occurring terrestrial invertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickx, Frederik; Maelfait, Jean-Pierre; Bogaert, Nicolas; Tojal, Catarina; Du Laing, Gijs; Tack, Filip M.G.; Verloo, Marc G

    2004-02-01

    As physicochemical properties of the soil highly influence the bioavailable fraction of a particular trace metal, measured metal body burdens in a particular species are often assumed to be more reliable estimators of the contamination of the biota. To test this we compared the Cd, Cu and Zn content of three spiders (generalist predators) and two amphipods (detritivores), co-occurring in seven tidal marshes along the river Schelde, between each other and with the total metal concentrations and the concentrations of four sequential extractions of the soils. Correlations were significant in only one case and significant sitexspecies interactions for all metals demonstrate that factors affecting metal concentration were species and site specific and not solely determined by site specific characteristics. These results emphasize that site and species specific biological factors might be of the utmost importance in determining the contamination of the biota, at least for higher trophic levels. A hypothetical example clarifies these findings. - Site and species specific biological factors are important in determining contamination of biota.

  2. Electrochemical oxidation of biological pretreated and membrane separated landfill leachate concentrates on boron doped diamond anode

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Bo, E-mail: 357436235@qq.com [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); Yu, Zhiming, E-mail: zhiming@csu.edu.cn [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); Wei, Qiuping, E-mail: qiupwei@csu.edu.cn [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); Long, HangYu, E-mail: 55686385@qq.com [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); Xie, Youneng, E-mail: 1187272844@qq.com [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); Wang, Yijia, E-mail: 503630433@qq.com [School of Materials Science and Engineering, Central South University, Changsha 410083 (China)

    2016-07-30

    Highlights: • High quality boron-doped diamond film electrodes were synthesized on Nb substrates. • Electrochemical oxidation on boron-doped diamond anode is an effective method for treating landfill leachate concentrates. • Optimal operating conditions for electrochemical oxidation of landfill leachate concentrates is determined. • 87.5% COD removal and 74.06% NH{sub 3}−N removal were achieved after 6 h treatment. - Abstract: In the present study, the high quality boron-doped diamond (BDD) electrodes with excellent electrochemical properties were deposited on niobium (Nb) substrates by hot filament chemical vapor deposition (HFCVD) method. The electrochemical oxidation of landfill leachate concentrates from disc tube reverse osmosis (DTRO) process over a BDD anode was investigated. The effects of varying operating parameters, such as current density, initial pH, flow velocity and cathode material on degradation efficiency were also evaluated following changes in chemical oxygen demand (COD) and ammonium nitrogen (NH{sub 3}−N). The instantaneous current efficiency (ICE) was used to appraise different operating conditions. As a result, the best conditions obtained were as follows, current density 50 mA cm{sup −2}, pH 5.16, flow velocity 6 L h{sup −1}. Under these conditions, 87.5% COD and 74.06% NH{sub 3}−N removal were achieved after 6 h treatment, with specific energy consumption of 223.2 kWh m{sup −3}. In short, these results indicated that the electrochemical oxidation with BDD/Nb anode is an effective method for the treatment of landfill leachate concentrates.

  3. Relevance analysis and short-term prediction of PM2.5 concentrations in Beijing based on multi-source data

    Science.gov (United States)

    Ni, X. Y.; Huang, H.; Du, W. P.

    2017-02-01

    The PM2.5 problem is proving to be a major public crisis and is of great public-concern requiring an urgent response. Information about, and prediction of PM2.5 from the perspective of atmospheric dynamic theory is still limited due to the complexity of the formation and development of PM2.5. In this paper, we attempted to realize the relevance analysis and short-term prediction of PM2.5 concentrations in Beijing, China, using multi-source data mining. A correlation analysis model of PM2.5 to physical data (meteorological data, including regional average rainfall, daily mean temperature, average relative humidity, average wind speed, maximum wind speed, and other pollutant concentration data, including CO, NO2, SO2, PM10) and social media data (microblog data) was proposed, based on the Multivariate Statistical Analysis method. The study found that during these factors, the value of average wind speed, the concentrations of CO, NO2, PM10, and the daily number of microblog entries with key words 'Beijing; Air pollution' show high mathematical correlation with PM2.5 concentrations. The correlation analysis was further studied based on a big data's machine learning model- Back Propagation Neural Network (hereinafter referred to as BPNN) model. It was found that the BPNN method performs better in correlation mining. Finally, an Autoregressive Integrated Moving Average (hereinafter referred to as ARIMA) Time Series model was applied in this paper to explore the prediction of PM2.5 in the short-term time series. The predicted results were in good agreement with the observed data. This study is useful for helping realize real-time monitoring, analysis and pre-warning of PM2.5 and it also helps to broaden the application of big data and the multi-source data mining methods.

  4. Element concentrations in candidate biological and environmental reference materials by k0-standardized INAA

    International Nuclear Information System (INIS)

    Freitas, M.C.

    1993-01-01

    K 0 -Based Neutron Activation Analysis (k 0 INAA) was used to analyze the candidate reference materials Apple Leaves and Peach Leaves, and Oriental Tobacco Leaves and Virginia Tobacco Leaves. Concentration values for 27 elements were measured. The accuracy was ascertained by analysis of two certified reference materials. NIST 1572 Citrus Leaves and 1573 Tomato Leaves. The homogeneity test of the IAEA Evernia prunastri candidate reference material in aliquots ≥ 100 mg is extended to the elements Sc, Cr, Fe, Co, Zn, Rb, Sb, Cs, Ba, Ce and Th. (orig.)

  5. Tenofovir alafenamide (TAF) does not deplete mitochondrial DNA in human T-cell lines at intracellular concentrations exceeding clinically relevant drug exposures.

    Science.gov (United States)

    Stray, Kirsten M; Park, Yeojin; Babusis, Darius; Callebaut, Christian; Cihlar, Tomas; Ray, Adrian S; Perron, Michel

    2017-04-01

    HIV-infected patients treated with certain nucleoside reverse transcriptase inhibitors (NRTIs) have experienced adverse effects due to drug-related mitochondrial toxicity. Tenofovir alafenamide (TAF) is a novel prodrug of the NRTI tenofovir (TFV) with an improved safety profile compared to tenofovir disoproxil fumarate (TDF). Prior in vitro studies have demonstrated that the parent nucleotide TFV has no significant effects on mtDNA synthesis. This study investigated whether clinically relevant TAF and TDF exposures affect mtDNA content in human lymphocytes. First, activated or resting peripheral blood mononuclear cells (PBMCs), as well as MT-2 and Jurkat T-cell lines, were continuously treated with ddC for 10 days to establish their susceptibility to mtDNA depletion. PBMCs had low sensitivity to NRTI-mediated mtDNA depletion in vitro. In contrast, ddC treatment of rapidly dividing MT-2 and Jurkat cells resulted in a dose-dependent decrease in mtDNA. Therefore, these two T-cell lines were selected for evaluating TAF and TDF treatment effects. MT-2 and Jurkat cells were pulse-treated with TAF or TDF every 24 h for 10 days to mimic pharmacologically relevant drug exposures. Pulse treatment of cells with 3.3 μM TAF or 1.1 μM TDF for 10 days resulted in 2- to 7-fold greater steady-state intracellular TFV-diphosphate (TFV-DP) levels than those observed clinically in TAF- or TDF-treated patients. At these concentrations, no significant TAF- (106.7% and 84.1% of control; p = 0.77 and 0.12 for MT-2 and Jurkat, respectively) or TDF- (100.6% and 91.0% of control; p = 0.91 and 0.37, respectively) associated reduction in mtDNA content was observed compared with untreated control cells. This study demonstrates that, despite delivering higher intracellular levels of TFV-DP than TDF, TAF does not inhibit mtDNA synthesis in vitro at concentrations exceeding the clinically relevant intracellular drug exposures. Thus, TAF has a low potential for mitochondrial toxicity in

  6. MAK and BAT values list 2014. Maximum permissible concentrations at the place of work and biological tolerance values for working materials

    International Nuclear Information System (INIS)

    2014-01-01

    The book on the MAK (maximum permissible concentrations at the place of work) and BAT (biological tolerance values for working materials) value list 2014 includes the following chapters: (a) Maximum permissible concentrations at the place of work: definition, application and determination of MAT values, list of materials; carcinogenic working materials, sensibilizing working materials, aerosols, limiting the exposition peaks, skin resorption, MAK values during pregnancy, germ cell mutagens, specific working materials; (b) Biological tolerance values for working materials: definition and application of BAT values, list of materials, carcinogenic working materials, biological guide values, biological working material reference values.

  7. MAK and BAT values list 2015. Maximum permissible concentrations at the place of work and biological tolerance values for working materials

    International Nuclear Information System (INIS)

    2015-01-01

    The book on the MAK (maximum permissible concentrations at the place of work) and BAT (biological tolerance values for working materials) value list 2015 includes the following chapters: (a) Maximum permissible concentrations at the place of work: definition, application and determination of MAT values, list of materials; carcinogenic working materials, sensibilizing working materials, aerosols, limiting the exposition peaks, skin resorption, MAK values during pregnancy, germ cell mutagens, specific working materials; (b) Biological tolerance values for working materials: definition and application of BAT values, list of materials, carcinogenic working materials, biological guide values, biological working material reference values.

  8. Low acetate concentrations favor polyphosphate-accumulating organisms over glycogen-accumulating organisms in enhanced biological phosphorus removal from wastewater.

    Science.gov (United States)

    Tu, Yunjie; Schuler, Andrew J

    2013-04-16

    Glycogen-accumulating organisms (GAOs) are thought to compete with polyphosphate-accumulating organisms (PAOs) in enhanced biological phosphorus removal (EBPR) wastewater treatment systems. A laboratory sequencing batch reactor (SBR) was operated for one year to test the hypothesis that PAOs have a competitive advantage at low acetate concentrations, with a focus on low pH conditions previously shown to favor GAOs. PAOs dominated the system under conventional SBR operation with rapid acetate addition (producing high in-reactor concentrations) and pH values of 7.4-8.4. GAOs dominated when the pH was decreased (6.4-7.0). Decreasing the acetate addition rate led to very low reactor acetate concentrations, and PAOs recovered, supporting the study hypothesis. When the acetate feed rate was increased, EBPR failed again. Dominant PAOs and GAOs were Candidatus Accumulibacter phosphatis and Defluviicoccus Cluster 2, respectively, according to fluorescent in situ hybridization and 454 pyrosequencing. Surprisingly, GAOs were not the immediate causes of PAO failures, based on functional and population measurements. Pyrosequencing results suggested Dechloromonas and Tetrasphaera spp. may have also been PAOs, and additional potential GAOs were also identified. Full-scale systems typically have lower in-reactor acetate concentrations than laboratory SBRs, and so, previous laboratory studies may have overestimated the practical importance of GAOs as causes of EBPR failure.

  9. Luminescent passive-oxidized silicon quantum dots as biological staining labels and their cytotoxicity effects at high concentration

    International Nuclear Information System (INIS)

    Fujioka, Kouki; Manabe, Noriyoshi; Hanada, Sanshiro; Hoshino, Akiyoshi; Yamamoto, Kenji; Hiruoka, Masaki; Sato, Keisuke; Hirakuri, Kenji; Miyasaka, Ryosuke; Tilley, Richard D; Manome, Yoshinobu

    2008-01-01

    Semiconductor quantum dots (QDs) hold some advantages over conventional organic fluorescent dyes. Due to these advantages, they are becoming increasingly popular in the field of bioimaging. However, recent work suggests that cadmium based QDs affect cellular activity. As a substitute for cadmium based QDs, we have developed photoluminescent stable silicon quantum dots (Si-QDs) with a passive-oxidation technique. Si-QDs (size: 6.5 ± 1.5 nm) emit green light, and they have been used as biological labels for living cell imaging. In order to determine the minimum concentration for cytotoxicity, we investigated the response of HeLa cells. We have shown that the toxicity of Si-QDs was not observed at 112 μg ml -1 and that Si-QDs were less toxic than CdSe-QDs at high concentration in mitochondrial assays and with lactate dehydrogenase (LDH) assays. Especially under UV exposure, Si-QDs were more than ten times safer than CdSe-QDs. We suggest that one mechanism for the cytotoxicity is that Si-QDs can generate oxygen radicals and these radicals are associated with membrane damages. This work has demonstrated the suitability of Si-QDs for bioimaging in lower concentration, and their cytotoxicity and one toxicity mechanism at high concentration

  10. Contextual Hub Analysis Tool (CHAT: A Cytoscape app for identifying contextually relevant hubs in biological networks [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Tanja Muetze

    2016-08-01

    Full Text Available Highly connected nodes (hubs in biological networks are topologically important to the structure of the network and have also been shown to be preferentially associated with a range of phenotypes of interest. The relative importance of a hub node, however, can change depending on the biological context. Here, we report a Cytoscape app, the Contextual Hub Analysis Tool (CHAT, which enables users to easily construct and visualize a network of interactions from a gene or protein list of interest, integrate contextual information, such as gene expression or mass spectrometry data, and identify hub nodes that are more highly connected to contextual nodes (e.g. genes or proteins that are differentially expressed than expected by chance. In a case study, we use CHAT to construct a network of genes that are differentially expressed in Dengue fever, a viral infection. CHAT was used to identify and compare contextual and degree-based hubs in this network. The top 20 degree-based hubs were enriched in pathways related to the cell cycle and cancer, which is likely due to the fact that proteins involved in these processes tend to be highly connected in general. In comparison, the top 20 contextual hubs were enriched in pathways commonly observed in a viral infection including pathways related to the immune response to viral infection. This analysis shows that such contextual hubs are considerably more biologically relevant than degree-based hubs and that analyses which rely on the identification of hubs solely based on their connectivity may be biased towards nodes that are highly connected in general rather than in the specific context of interest.   Availability: CHAT is available for Cytoscape 3.0+ and can be installed via the Cytoscape App Store (http://apps.cytoscape.org/apps/chat.

  11. p,p'-DDE Induces Gonadal Intersex in Japanese Medaka (Oryzias latipes) at Environmentally Relevant Concentrations: Comparison with o,p'-DDT.

    Science.gov (United States)

    Sun, Jianxian; Wang, Chen; Peng, Hui; Zheng, Guomao; Zhang, Shiyi; Hu, Jianying

    2016-01-05

    Previous studies have reported high body burdens of dichlorodiphenyltrichloroethane (DDT) and its metabolites in wild fishes worldwide. This study evaluated the adverse effects of 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE) and o,p'-DDT on gonadal development and reproduction by exposing transgenic Japanese medaka (Oryzias latipes) from hatch for 100 days. While both p,p'-DDE and o,p'-DDT induced intersex in male medaka, the lowest observable effective concentration (LOEC) of o,p'-DDT was 57.7 ng/g ww, about 5-fold lower than that (272 ng/g ww) of p,p'-DDE. Since LOECs of both chemicals were comparable to the body concentrations in wild fish, DDT contamination would likely contribute to the occurrence of intersex observed in wild fish. Exposure to o,p'-DDT resulted in much higher expression of vitellogenin in liver of males than p,p'-DDE, accordant with the higher potency of o,p'-DDT than p,p'-DDE to induce intersex. This phenomenon could be partly explained by the significantly elevated levels of 17β-estradiol in plasma of males exposed to o,p'-DDT, in addition to its estrogenic activity via the estrogen receptor. Significantly lower fertilization (p = 0.006) and hatchability (p = 0.019) were observed in the 13 intersex males. This study for the first time demonstrated the induction of intersex and reproductive effects of p,p'-DDE and o,p'-DDT at environmentally relevant concentrations.

  12. The intake of water containing a mix of pollutants at environmentally relevant concentrations leads to defensive response deficit in male C57Bl/6J mice.

    Science.gov (United States)

    de Souza, Joyce Moreira; Rabelo, Letícia Martins; de Faria, Denise Braga Gomes; Guimarães, Abraão Tiago Batista; da Silva, Wellington Alves Mizael; Rocha, Thiago Lopes; Estrela, Fernanda Neves; Chagas, Thales Quintão; de Oliveira Mendes, Bruna; Malafaia, Guilherme

    2018-07-01

    Previous studies have individually confirmed the toxic effects from different pollutants on mammals. However, effects resulting from the exposure of these animals to multi-pollutant mixes have not been studied so far. Thus, the aim of the current study is to assess the effect from the chronic exposure (105days) of C57Bl/6J mice to a mix of pollutants on their response to potential predators. In order to do so, the following groups were formed: "control", "Mix 1× [compounds from 15 pollutants identified in surface waters at environmentally relevant concentration (ERC)]", "Mix 10×" and "Mix 25×" (concentrations 10 and 25 times higher than the ERC). From the 100th experimental day on, the animals were subjected to tests in order to investigate whether they showed locomotor, visual, olfactory and auditory changes, since these abilities are essential to their anti-predatory behavior. Next, the animals' behavior towards potential predators (Felis catus and Pantherophis guttatus) was assessed. The herein collected data did not show defensive response from any of the experimental groups to the predatory stimulus provided by P. guttatus. However, the control animals, only, presented anti-predatory behavior when F. catus was introduced in the apparatus, fact that suggests defensive response deficit resulting from the treatments. Thus, the current study is pioneer in showing that the chronic intake of water containing a mix of pollutants (even at low concentrations) leads to behavioral disorders able to affect the survival and population dynamics of mammalian species at ecological level. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Concentration and characteristics of depleted uranium in water, air and biological samples collected in Serbia and Montenegro

    International Nuclear Information System (INIS)

    Jia Guogang; Belli, Maria; Sansone, Umberto; Rosamilia, Silvia; Gaudino, Stefania

    2005-01-01

    During the Balkan conflicts, in 1995 and 1999, depleted uranium (DU) rounds were employed and were left in the battlefield. Health concern is related to the risk arising from contamination of the environment with DU penetrators and dust. In order to evaluate the impact of DU on the environment and population in Serbia and Montenegro, radiological surveys of DU in water, air and biological samples were carried out over the period 27 October-5 November 2001. The uranium isotopic concentrations in biological samples collected in Serbia and Montenegro, mainly lichens and barks, were found to be in the range of 0.67-704 Bq kg -1 for 238 U, 0.48-93.9 Bq kg -1 for 234 U and 0.02-12.2 Bq kg -1 for 235 U, showing uranium levels to be higher than in the samples collected at the control sites. Moreover, 236 U was detectable in some of the samples. The isotopic ratios of 234 U/ 238 U showed DU to be detectable in many biological samples at all examined sites, especially in Montenegro, indicating widespread ground-surface DU contamination, albeit at very low level. The uranium isotopic concentrations in air obtained from the air filter samples collected in Serbia and Montenegro were found to be in the range of 1.99-42.1 μBq m -3 for 238 U, 0.96-38.0 μBq m -3 for 234 U, and 0.05-1.83 μBq m -3 for 235 U, being in the typical range of natural uranium values. Thus said, most of the air samples are DU positive, this fact agreeing well with the widespread DU contamination detected in the biological samples. The uranium concentrations in water samples collected in Serbia and Montenegro were found to be in the range of 0.40-21.9 mBq l -1 for 238 U, 0.27-28.1 mBq l -1 for 234 U, and 0.01-0.88 mBq l -1 for 235 U, these values being much lower than those in mineral water found in central Italy and below the WHO guideline for drinking water. From a radiotoxicological point of view, at this moment there is no significant radiological risk related to these investigated sites in terms of

  14. Concentration and characteristics of depleted uranium in water, air and biological samples collected in Serbia and Montenegro.

    Science.gov (United States)

    Jia, Guogang; Belli, Maria; Sansone, Umberto; Rosamilia, Silvia; Gaudino, Stefania

    2005-09-01

    During the Balkan conflicts, in 1995 and 1999, depleted uranium (DU) rounds were employed and were left in the battlefield. Health concern is related to the risk arising from contamination of the environment with DU penetrators and dust. In order to evaluate the impact of DU on the environment and population in Serbia and Montenegro, radiological surveys of DU in water, air and biological samples were carried out over the period 27 October-5 November 2001. The uranium isotopic concentrations in biological samples collected in Serbia and Montenegro, mainly lichens and barks, were found to be in the range of 0.67-704 Bqkg(-1) for (238)U, 0.48-93.9 Bqkg(-1) for (234)U and 0.02-12.2 Bqkg(-1) for (235)U, showing uranium levels to be higher than in the samples collected at the control sites. Moreover, (236)U was detectable in some of the samples. The isotopic ratios of (234)U/(238)U showed DU to be detectable in many biological samples at all examined sites, especially in Montenegro, indicating widespread ground-surface DU contamination, albeit at very low level. The uranium isotopic concentrations in air obtained from the air filter samples collected in Serbia and Montenegro were found to be in the range of 1.99-42.1 microBqm(-3) for (238)U, 0.96-38.0 microBqm(-3) for (234)U, and 0.05-1.83 microBqm(-3) for (235)U, being in the typical range of natural uranium values. Thus said, most of the air samples are DU positive, this fact agreeing well with the widespread DU contamination detected in the biological samples. The uranium concentrations in water samples collected in Serbia and Montenegro were found to be in the range of 0.40-21.9 mBql(-1) for (238)U, 0.27-28.1 mBql(-1) for (234)U, and 0.01-0.88 mBql(-1) for (235)U, these values being much lower than those in mineral water found in central Italy and below the WHO guideline for drinking water. From a radiotoxicological point of view, at this moment there is no significant radiological risk related to these investigated

  15. Making Biology Relevant to Undergraduates

    Science.gov (United States)

    Musante, Susan

    2012-01-01

    This article features Science Education for New Civic Engagements and Responsibilities (SENCER; www.sencer.net) Summer Institute. The SENCER program, which began formally in 2001, was the vision of David Burns; Karen Oates, currently Peterson Family Dean of Arts and Sciences at Worcester Polytechnic Institute; and Ric Wiebl, currently director of…

  16. [Biologic effects of different concentrations of putrescine on human umbilical vein endothelial cells].

    Science.gov (United States)

    Chen, Jianxia; Rong, Xinzhou; Fan, Guicheng; Li, Songze; Zhang, Tao; Li, Qinghui

    2015-12-01

    To explore the effects of different concentrations of putrescine on proliferation, migration, and apoptosis of human umbilical vein endothelial cells (HUVECs). HUVECs were routinely cultured in vitro. The 3rd to the 5th passage of HUVECs were used in the following experiments. (1) Cells were divided into 500, 1 000, and 5 000 µg/mL putrescine groups according to the random number table (the same grouping method was used for following grouping), with 3 wells in each group, which were respectively cultured with complete culture solution containing putrescine in the corresponding concentration for 24 h. Morphology of cells was observed by inverted optical microscope. (2) Cells were divided into 0.5, 1.0, 5.0, 10.0, 50.0, 100.0, 500.0, 1 000.0 µg/mL putrescine groups, and control group, with 4 wells in each group. Cells in the putrescine groups were respectively cultured with complete culture solution containing putrescine in the corresponding concentration for 24 h, and cells in control group were cultured with complete culture solution with no additional putrescine for 24 h. Cell proliferation activity (denoted as absorption value) was measured by colorimetry. (3) Cells were divided (with one well in each group) and cultured as in experiment (2), and the migration ability was detected by transwell migration assay. (4) Cells were divided (with one flask in each group) and cultured as in experiment (2), and the cell apoptosis rate was determined by flow cytometer. Data were processed with one-way analysis of variance, Kruskal-Wallis test, and Dunnett test. (1) After 24-h culture, cell attachment was good in 500 µg/mL putrescine group, and no obvious change in the shape was observed; cell attachment was less in 1 000 µg/mL putrescine group and the cells were small and rounded; cells in 5 000 µg/mL putrescine group were in fragmentation without attachment. (2) The absorption values of cells in 0.5, 1.0, 5.0, 10.0, 50.0, 100.0, 500.0, 1 000.0 µg/mL putrescine groups

  17. A biological indicator of inorganic arsenic exposure using the sum of urinary inorganic arsenic and monomethylarsonic acid concentrations

    Science.gov (United States)

    Hata, Akihisa; Kurosawa, Hidetoshi; Endo, Yoko; Yamanaka, Kenzo; Fujitani, Noboru; Endo, Ginji

    2016-01-01

    Objectives: The sum of urinary inorganic arsenic (iAs), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) concentrations is used for the biological monitoring of occupational iAs exposure. Although DMA is a major metabolite of iAs, it is an inadequate index because high DMA levels are present in urine after seafood consumption. We estimated the urinary iAs+MMA concentration corresponding to iAs exposure. Methods: We used data from two arsenic speciation analyses of urine samples from 330 Bangladeshi with oral iAs exposure and 172 Japanese workers without occupational iAs exposure using high-performance liquid chromatography with inductively coupled plasma mass spectrometry. Results: iAs, MMA, and DMA, but not arsenobetaine (AsBe), were detected in the urine of the Bangladeshi subjects. The correlation between iAs+MMA+DMA and iAs+MMA was obtained as log (iAs+MMA) = 1.038 log (iAs+MMA+DMA) -0.658. Using the regression formula, the iAs+MMA value was calculated as 2.15 and 7.5 μg As/l, corresponding to 3 and 10 μg As/m3 of exposures, respectively. In the urine of the Japanese workers, arsenic was mostly excreted as AsBe. We used the 95th percentile of iAs+MMA (12.6 μg As/l) as the background value. The sum of the calculated and background values can be used as a biological indicator of iAs exposure. Conclusion: We propose 14.8 and 20.1 μg As/l of urinary iAs+MMA as the biological indicators of 3 and 10 μg As/m3 iAs exposure, respectively. PMID:27010090

  18. Biological nitrogen and carbon removal in a gravity flow biomass concentrator reactor for municipal sewage treatment.

    Science.gov (United States)

    Scott, Daniel; Hidaka, Taira; Campo, Pablo; Kleiner, Eric; Suidan, Makram T; Venosa, Albert D

    2013-01-01

    A novel membrane system, the Biomass Concentrator Reactor (BCR), was evaluated as an alternative technology for the treatment of municipal wastewater. Because the BCR is equipped with a membrane whose average poresize is 20 μm (18-28 μm), the reactor requires low-pressure differential to operate (gravity). The effectiveness of this system was evaluated for the removal of carbon and nitrogen using two identical BCRs, identified as conventional and hybrid, that were operated in parallel. The conventional reactor was operated under full aerobic conditions (i.e., organic carbon and ammonia oxidation), while the hybrid reactor incorporated an anoxic zone for nitrate reduction as well as an aerobic zone for organic carbon and ammonia oxidation. Both reactors were fed synthetic wastewater at a flow rate of 71 L d(-1), which resulted in a hydraulic retention time of 9 h. In the case of the hybrid reactor, the recycle flow from the aerobic zone to the anoxic zone was twice the feed flow rate. Reactor performance was evaluated under two solids retention times (6 and 15 d). Under these conditions, the BCRs achieved nearly 100% mixed liquor solids separation with a hydraulic head differential of less than 2.5 cm. The COD removal efficiency was over 90%. Essentially complete nitrification was achieved in both systems, and nitrogen removal in the hybrid reactor was close to the expected value (67%). Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Alcohol intoxication at Swedish football matches: A study using biological sampling to assess blood alcohol concentration levels among spectators.

    Directory of Open Access Journals (Sweden)

    Natalie Durbeej

    Full Text Available Alcohol use and alcohol-related problems, including accidents, vandalism and violence, at sporting events are of increased concern in Sweden and other countries. The relationship between alcohol use and violence has been established and can be explained by the level of intoxication. Given the occurrence of alcohol use and alcohol-related problems at sporting events, research has assessed intoxication levels measured through biological sampling among spectators. This cross-sectional study aimed to assess the level of alcohol intoxication among spectators at football matches in the Swedish Premier Football League. Spectators were randomly selected and invited to participate in the study. Alcohol intoxication was measured with a breath analyser for Blood Alcohol Concentration levels, and data on gender, age, and recent alcohol use were gathered through a face-to-face interview. Blood Alcohol Concentration samples from 4420 spectators were collected. Almost half (46.8% had a positive Blood Alcohol Concentration level, with a mean value of 0.063%, while 8.9% had a Blood Alcohol Concentration level ≥ 0.1%, with a mean value of 0.135%. Factors that predicted a higher Blood Alcohol Concentration level included male gender (p = 0.005, lower age (p < 0.001, attending a local derby (p < 0.001, alcohol use prior to having entered the arena (p < 0.001, attending a weekend match (p < 0.001, and being a spectator at supporter sections (p < 0.001. About half of all spectators at football matches in the Swedish Premier Football League drink alcohol in conjunction with the match. Approximately one tenth have a high level of alcohol intoxication.

  20. Biological and life-history factors affecting total mercury concentrations in Arctic charr from Heintzelman Lake, Ellesmere Island, Nunavut

    International Nuclear Information System (INIS)

    Velden, Shannon van der; Reist, James D.; Babaluk, John A.; Power, Michael

    2012-01-01

    A snapshot sample of Arctic charr (Salvelinus alpinus) from Heintzelman Lake (81°42′N, 66°56′W), Ellesmere Island, Canada was used to elucidate the biological and life-history factors potentially influencing individual total mercury (THg) concentrations. Migratory history was significant, with anadromous fish having a lower mean THg concentration (64 μg/kg ww) than the non-anadromous Arctic charr (117 μg/kg ww). The increase in individual THg concentration with age was shown to be independent of length-at-age when large and small individuals within the same age groups were compared. Similarly, the diets of individual Arctic charr were comparable regardless of size, and there was no apparent ontogenetic shift in diet that could explain differences in length-at-age or THg concentration among fast- and slow-growing groups of fish (i.e., fish of the same age but differing sizes). Maturity state was also not related to THg concentration, but appears to be related to differences in length-at-age, with slow-growing fish allocating more energy to reproduction than fast-growing conspecifics. The differences in THg concentration among individual Arctic charr were best explained by fish age. We suggest that the increase in mercury concentration with age can be altered by a shift in diet (e.g., to piscivory) or habitat (e.g., anadromy), but is otherwise unaffected by changes in size or length-at-age. -- Highlights: ► Total mercury concentrations ([THg]) were measured in Arctic charr from a single lake in the Canadian high Arctic. ► Anadromous Arctic charr had a significantly lower mean [THg] (64 μg/kg ww) than the non-anadromous fish (117 μg/kg ww). ► Length-at-age (i.e., average somatic growth rate) was not related to mean [THg] when same-age groups were compared. ► Prey resource use, determined by δ 13 C and δ 15 N isotopes and gut contents, was similar among fast- and slow-growing fish. ► Maturity state was not related to [THg], but the slow

  1. Tertiary treatment of textile wastewater with combined media biological aerated filter (CMBAF) at different hydraulic loadings and dissolved oxygen concentrations

    International Nuclear Information System (INIS)

    Liu Fang; Zhao Chaocheng; Zhao Dongfeng; Liu Guohua

    2008-01-01

    An up-flow biological aerated filter packed with two layers media was employed for tertiary treatment of textile wastewater secondary effluent. Under steady state conditions, good performance of the reactor was achieved and the average COD, NH 4 + -N and total nitrogen (TN) in the effluent were 31, 2 and 8 mg/L, respectively. For a fixed dissolved oxygen (DO) concentration, an increase of hydraulic loading resulted in a decrease in substrate removal. With the increase of hydraulic loadings from 0.13 to 0.78 m 3 /(m 2 h), the removal efficiencies of COD, NH 4 + -N and TN all decreased, which dropped from 52 to 38%, from 90 to 68% and from 45 to 33%, respectively. In addition, the results also confirmed that the increase of COD and NH 4 + -N removal efficiencies resulted from the increase of DO concentrations, but this variation trend was not observed for TN removal. With the increase of DO concentrations from 2.4 to 6.1 mg/L, the removal efficiencies of COD and NH 4 + -N were 39-53% and 64-88%, whenas TN removal efficiencies increased from 39 to 42% and then dropped to 35%

  2. Clinically Relevant Plasma Concentrations of Colistin in Combination with Imipenem Enhance Pharmacodynamic Activity against Multidrug-Resistant Pseudomonas aeruginosa at Multiple Inocula▿†

    Science.gov (United States)

    Bergen, Phillip J.; Forrest, Alan; Bulitta, Jürgen B.; Tsuji, Brian T.; Sidjabat, Hanna E.; Paterson, David L.; Li, Jian; Nation, Roger L.

    2011-01-01

    The use of combination antibiotic therapy may be beneficial against rapidly emerging resistance in Pseudomonas aeruginosa. The aim of this study was to systematically investigate in vitro bacterial killing and resistance emergence with colistin alone and in combination with imipenem against multidrug-resistant (MDR) P. aeruginosa. Time-kill studies were conducted over 48 h using 5 clinical isolates and ATCC 27853 at two inocula (∼106 and ∼108 CFU/ml); MDR, non-MDR, and colistin-heteroresistant and -resistant strains were included. Nine colistin-imipenem combinations were investigated. Microbiological response was examined by log changes at 6, 24, and 48 h. Colistin combined with imipenem at clinically relevant concentrations increased the levels of killing of MDR and colistin-heteroresistant isolates at both inocula. Substantial improvements in activity with combinations were observed across 48 h with all colistin concentrations at the low inoculum and with colistin at 4× and 16× MIC (or 4 and 32 mg/liter) at the high inoculum. Combinations were additive or synergistic against imipenem-resistant isolates (MICs, 16 and 32 mg/liter) at the 106-CFU inoculum in 9, 11, and 12 of 18 cases (i.e., 9 combinations across 2 isolates) at 6, 24, and 48 h, respectively, and against the same isolates at the 108-CFU inoculum in 11, 7, and 8 cases, respectively. Against a colistin-resistant strain (MIC, 128 mg/liter), combinations were additive or synergistic in 9 and 8 of 9 cases at 24 h at the 106- and 108-CFU inocula, respectively, and in 5 and 7 cases at 48 h. This systematic study provides important information for optimization of colistin-imipenem combinations targeting both colistin-susceptible and colistin-resistant subpopulations. PMID:21876058

  3. Nonproteinogenic D-amino acids at millimolar concentrations are a toxin for anaerobic microorganisms relevant to early Earth and other anoxic planets.

    Science.gov (United States)

    Nixon, Sophie L; Cockell, Charles S

    2015-03-01

    The delivery of extraterrestrial organics to early Earth provided a potentially important source of carbon and energy for microbial life. Optically active organic compounds of extraterrestrial origin exist in racemic form, yet life on Earth has almost exclusively selected for L- over D-enantiomers of amino acids. Although D-enantiomers of proteinogenic amino acids are known to inhibit aerobic microorganisms, the role of concentrated nonproteinogenic meteoritic D-amino acids on anaerobic metabolisms relevant to early Earth and other anoxic planets such as Mars is unknown. Here, we test the inhibitory effect of D-enantiomers of two nonproteinogenic amino acids common to carbonaceous chondrites, norvaline and α-aminobutyric acid, on microbial iron reduction. Three pure strains (Geobacter bemidjiensis, Geobacter metallireducens, Geopsychrobacter electrodiphilus) and an iron-reducing enrichment culture were grown in the presence of 10 mM D-enantiomers of both amino acids. Further tests were conducted to assess the inhibitory effect of these D-amino acids at 1 and 0.1 mM. The presence of 10 mM D-norvaline and D-α-aminobutyric acid inhibited microbial iron reduction by all pure strains and the enrichment. G. bemidjiensis was not inhibited by either amino acid at 0.1 mM, but D-α-aminobutyric acid still inhibited at 1 mM. Calculations using published meteorite accumulation rates to the martian surface indicate D-α-aminobutyric acid may have reached inhibitory concentrations in little over 1000 years during peak infall. These data show that, on a young anoxic planet, the use of one enantiomer over another may render the nonbiological enantiomer an environmental toxin. Processes that generate racemic amino acids in the environment, such as meteoritic infall or impact synthesis, would have been toxic processes and could have been a selection pressure for the evolution of early racemases.

  4. Food words distract the hungry: Evidence of involuntary semantic processing of task-irrelevant but biologically-relevant unexpected auditory words.

    Science.gov (United States)

    Parmentier, Fabrice B R; Pacheco-Unguetti, Antonia P; Valero, Sara

    2018-01-01

    Rare changes in a stream of otherwise repeated task-irrelevant sounds break through selective attention and disrupt performance in an unrelated visual task by triggering shifts of attention to and from the deviant sound (deviance distraction). Evidence indicates that the involuntary orientation of attention to unexpected sounds is followed by their semantic processing. However, past demonstrations relied on tasks in which the meaning of the deviant sounds overlapped with features of the primary task. Here we examine whether such processing is observed when no such overlap is present but sounds carry some relevance to the participants' biological need to eat when hungry. We report the results of an experiment in which hungry and satiated participants partook in a cross-modal oddball task in which they categorized visual digits (odd/even) while ignoring task-irrelevant sounds. On most trials the irrelevant sound was a sinewave tone (standard sound). On the remaining trials, deviant sounds consisted of spoken words related to food (food deviants) or control words (control deviants). Questionnaire data confirmed state (but not trait) differences between the two groups with respect to food craving, as well as a greater desire to eat the food corresponding to the food-related words in the hungry relative to the satiated participants. The results of the oddball task revealed that food deviants produced greater distraction (longer response times) than control deviants in hungry participants while the reverse effect was observed in satiated participants. This effect was observed in the first block of trials but disappeared thereafter, reflecting semantic saturation. Our results suggest that (1) the semantic content of deviant sounds is involuntarily processed even when sharing no feature with the primary task; and that (2) distraction by deviant sounds can be modulated by the participants' biological needs.

  5. N,N'-Dimethylthiourea dioxide formation from N,N'-dimethylthiourea reflects hydrogen peroxide concentrations in simple biological systems

    International Nuclear Information System (INIS)

    Curtis, W.E.; Muldrow, M.E.; Parker, N.B.; Barkley, R.; Linas, S.L.; Repine, J.E.

    1988-01-01

    The authors hypothesized that measurement of a specific product from reaction of N,N'-dimethylthiourea (Me 2 TU) and H 2 O 2 would provide a good indication of the H 2 O 2 scavenging and protection seen after addition of Me 2 TU to biological systems. They found that addition of H 2 O 2 to Me 2 TU yielded a single stable product, Me 2 TU dioxide. Me 2 TU dioxide formation correlated with Me 2 TU consumption as a function of added H 2 O 2 concentration and was prevented by simultaneous addition of catalase (but not boiled catalase), superoxide dismutase, dimethyl sulfoxide, mannitol, or sodium benzoate. Me 2 TU dioxide formation, Me 2 TU consumption, and H 2 O 2 concentration increases occurred in mixtures containing phorbol 12-myristate 13-acetate (PMA) and normal human neutrophils but not in mixtures containing PMA and neutrophils from patients with chronic granulomatous disease or in mixtures containing PMA and normal neutrophils and catalase. Me 2 TU dioxide formation also occurred in isolated rat lungs perfused with Me 2 TU and H 2 O 2 but not in lungs perfused with Me 2 TU and elastase, histamine, or oleic acid. In contrast, Me 2 TU dioxide formation did not occur after exposure of Me 2 TU to 60 Co-generated hydroxyl radical or hypochlorous acid in the presence of catalase. The results indicate that reaction of Me 2 TU with H 2 O 2 selectively forms Me 2 TU may be useful for assessing the presence and significance of H 2 O 2 in biological systems

  6. MAK and BAT values list 2016. Maximum permissible concentrations at the place of work and biological tolerance values for working materials

    International Nuclear Information System (INIS)

    2016-01-01

    The MAK and BAT values list 2016 includes the maximum permissible concentrations at the place of work and biological tolerance values for working materials. The following working materials are covered: carcinogenic working materials, sensitizing materials and aerosols. The report discusses the restriction of exposure peaks, skin resorption, MAK (maximum working place concentration) values during pregnancy, germ cell mutagens and specific working materials. Importance and application of BAT (biological working material tolerance) values, list of materials, carcinogens, biological guide values and reference values are also included.

  7. MAK and BAT values list 2017. Maximum permissible concentrations at the place of work and biological tolerance values for working materials

    International Nuclear Information System (INIS)

    2017-01-01

    The MAK and BAT values list 2017 includes the maximum permissible concentrations at the place of work and biological tolerance values for working materials. The following working materials are covered: carcinogenic working materials, sensitizing materials and aerosols. The report discusses the restriction of exposure peaks, skin resorption, MAK (maximum working place concentration) values during pregnancy, germ cell mutagens and specific working materials. Importance and application of BAT (biological working material tolerance) values, list of materials, carcinogens, biological guide values and reference values are also included.

  8. The Androgen-Regulated Calcium-Activated Nucleotidase 1 (CANT1) Is Commonly Overexpressed in Prostate Cancer and Is Tumor-Biologically Relevant in Vitro

    Science.gov (United States)

    Gerhardt, Josefine; Steinbrech, Corinna; Büchi, Oralea; Behnke, Silvia; Bohnert, Annette; Fritzsche, Florian; Liewen, Heike; Stenner, Frank; Wild, Peter; Hermanns, Thomas; Müntener, Michael; Dietel, Manfred; Jung, Klaus; Stephan, Carsten; Kristiansen, Glen

    2011-01-01

    Previously, we identified the calcium-activated nucleotidase 1 (CANT1) transcript as up-regulated in prostate cancer. Now, we studied CANT1 protein expression in a large cohort of nearly 1000 prostatic tissue samples including normal tissue, prostatic intraepithelial neoplasia (PIN), primary carcinomas, metastases, and castrate-resistant carcinomas, and further investigated its functional relevance. CANT1 displayed predominantly a Golgi-type immunoreactivity with additional and variable cytoplasmic staining. In comparison to normal tissues, the staining intensity was significantly increased in PIN lesions and cancer. In cancer, high CANT1 levels were associated with a better prognosis, and castrate-resistant carcinomas commonly showed lower CANT1 levels than primary carcinomas. The functional role of CANT1 was investigated using RNA interference in two prostate cancer cell lines with abundant endogenous CANT1 protein. On CANT1 knockdown, a significantly diminished cell number and DNA synthesis rate, a cell cycle arrest in G1 phase, and a strong decrease of cell transmigration rate and wound healing capacity of CANT1 knockdown cells was found. However, on forced CANT1 overexpression, cell proliferation and migration remained unchanged. In summary, CANT1 is commonly overexpressed in the vast majority of primary prostate carcinomas and in the precursor lesion PIN and may represent a novel prognostic biomarker. Moreover, this is the first study to demonstrate a functional involvement of CANT1 in tumor biology. PMID:21435463

  9. Correlation between γ-ray-induced DNA double-strand breakage and cell killing after biologically relevant doses: analysis by pulsed-field gel electrophoresis

    International Nuclear Information System (INIS)

    Murray, D.

    1994-01-01

    We examined the degree of correlation between γ-ray-induced lethality and DNA double-strand breaks (dsbs) after biologically relevant doses of radiation. Radiation lethality was modified by treating 14 C-labelled Chinese hamster ovary cells with either of two aminothiols (WR-1065 or WR-255591) and the associated effect on dsb induction was determined by pulsed-field gel electrophoresis (PFGE). The use of phosphorimaging to analyse the distribution of 14 C-activity in the gel greatly improved the low-dose resolution of the PFGE assay. Both WR-1065 and WR-255591 protected against dsb induction and lethality to a similar extent after low doses of radiation. although this correlation broke down when supralethal doses were used to induce dsbs. Thus, the level of dsbs induced in these cells as measured by PFGE after survival-curve doses of γ-radiation is consistently predictive of the degree of lethality obtained, implying a cause-effect relationship between these two parameters and confirming previous results obtained using the neutral filter elution assay for dsbs. (author)

  10. Digital ELISA for the quantification of attomolar concentrations of Alzheimer's disease biomarker protein Tau in biological samples.

    Science.gov (United States)

    Pérez-Ruiz, Elena; Decrop, Deborah; Ven, Karen; Tripodi, Lisa; Leirs, Karen; Rosseels, Joelle; van de Wouwer, Marlies; Geukens, Nick; De Vos, Ann; Vanmechelen, Eugeen; Winderickx, Joris; Lammertyn, Jeroen; Spasic, Dragana

    2018-07-26

    The close correlation between Tau pathology and Alzheimer's disease (AD) progression makes this protein a suitable biomarker for diagnosis and monitoring of the disorder evolution. However, the use of Tau in diagnostics has been hampered, as it currently requires collection of cerebrospinal fluid (CSF), which is an invasive clinical procedure. Although measuring Tau-levels in blood plasma would be favorable, the concentrations are below the detection limit of a conventional ELISA. In this work, we developed a digital ELISA for the quantification of attomolar protein Tau concentrations in both buffer and biological samples. Individual Tau molecules were first captured on the surface of magnetic particles using in-house developed antibodies and subsequently isolated into the femtoliter-sized wells of a 2 × 2 mm 2 microwell array. Combination of high-affinity antibodies, optimal assay conditions and a digital quantification approach resulted in a 24 ± 7 aM limit of detection (LOD) in buffer samples. Additionally, a dynamic range of 6 orders of magnitude was achieved by combining the digital readout with an analogue approach, allowing quantification from attomolar to picomolar levels of Tau using the same platform. This proves the compatibility of the presented assay with the wide range of Tau concentrations encountered in different biological samples. Next, the developed digital assay was applied to detect total Tau levels in spiked blood plasma. A similar LOD (55 ± 29 aM) was obtained compared to the buffer samples, which was 5000-fold more sensitive than commercially available ELISAs and even outperformed previously reported digital assays with 10-fold increase in sensitivity. Finally, the performance of the developed digital ELISA was assessed by quantifying protein Tau in three clinical CSF samples. Here, a high correlation (i.e. Pearson coefficient of 0.99) was found between the measured percentage of active particles and the reference protein Tau

  11. The mixture of "ecstasy" and its metabolites impairs mitochondrial fusion/fission equilibrium and trafficking in hippocampal neurons, at in vivo relevant concentrations.

    Science.gov (United States)

    Barbosa, Daniel José; Serrat, Romàn; Mirra, Serena; Quevedo, Martí; de Barreda, Elena Goméz; Àvila, Jesús; Ferreira, Luísa Maria; Branco, Paula Sério; Fernandes, Eduarda; Lourdes Bastos, Maria de; Capela, João Paulo; Soriano, Eduardo; Carvalho, Félix

    2014-06-01

    3,4-Methylenedioxymethamphetamine (MDMA; "ecstasy") is a potentially neurotoxic recreational drug of abuse. Though the mechanisms involved are still not completely understood, formation of reactive metabolites and mitochondrial dysfunction contribute to MDMA-related neurotoxicity. Neuronal mitochondrial trafficking, and their targeting to synapses, is essential for proper neuronal function and survival, rendering neurons particularly vulnerable to mitochondrial dysfunction. Indeed, MDMA-associated disruption of Ca(2+) homeostasis and ATP depletion have been described in neurons, thus suggesting possible MDMA interference on mitochondrial dynamics. In this study, we performed real-time functional experiments of mitochondrial trafficking to explore the role of in situ mitochondrial dysfunction in MDMA's neurotoxic actions. We show that the mixture of MDMA and six of its major in vivo metabolites, each compound at 10μM, impaired mitochondrial trafficking and increased the fragmentation of axonal mitochondria in cultured hippocampal neurons. Furthermore, the overexpression of mitofusin 2 (Mfn2) or dynamin-related protein 1 (Drp1) K38A constructs almost completely rescued the trafficking deficits caused by this mixture. Finally, in hippocampal neurons overexpressing a Mfn2 mutant, Mfn2 R94Q, with impaired fusion and transport properties, it was confirmed that a dysregulation of mitochondrial fission/fusion events greatly contributed to the reported trafficking phenotype. In conclusion, our study demonstrated, for the first time, that the mixture of MDMA and its metabolites, at concentrations relevant to the in vivo scenario, impaired mitochondrial trafficking and increased mitochondrial fragmentation in hippocampal neurons, thus providing a new insight in the context of "ecstasy"-induced neuronal injury.

  12. Environmentally relevant concentrations of di(2-ethylhexyl)phthalate exposure alter larval growth and locomotion in medaka fish via multiple pathways.

    Science.gov (United States)

    Yang, Wen-Kai; Chiang, Li-Fen; Tan, Shi-Wei; Chen, Pei-Jen

    2018-06-01

    Di(2-ethylhexyl)phthalate (DEHP) is a commonly used plasticizer, with evidence of ubiquitous human exposure and widespread occurrence in the aquatic environment. It is an emerging environmental pollutant with regulatory priority; however, most studies have focused on the toxicity of DEHP related to endocrine disruption and reproduction in mammals. The ecotoxicological impact of phthalates (e.g., DEHP) on early life stages of fish under environmentally relevant concentrations of chronic exposure remains unclear. In this study, 7-day post-hatching fry of medaka fish (Oryzias latipes) underwent 21-day continuous exposure to DEHP solutions at 20, 100 and 200 μg/L to assess the effects on fish development and locomotion and related toxic mechanisms. Larval mortality was low with DEHP (20-200 μg/L) within 21 days, but such exposure significantly reduced fish body weight and length and altered swimming behavior. At 21 days, DEHP exposure resulted in specific patterns of larval locomotion (e.g., increased maximum velocity and absolute turn angle) and dose-dependently increased the mRNA expression of acetylcholinesterase (ache) but did not alter AChE activity. Transcriptional expression of antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase and peroxisome proliferation-activated receptor and retinoid X receptor genes was significantly suppressed with 21-day DEHP exposure (20-200 μg/L), with marginal alteration in reactive oxygen species levels and antioxidant activities within the dosing period. As well, DEHP altered the mRNA expression of p53-regulated apoptosis pathways, such as upregulated p53, p21 and bcl-2 and downregulated caspase-3 expression, with increased enzymatic activity of caspase-3 in larvae. Our results suggest that toxic mechanisms of waterborne DEHP altered fish growth and locomotion likely via a combined effect of oxidative stress, neurotoxicity and apoptosis pathways. Copyright © 2018

  13. Identifying novel genes and biological processes relevant to the development of cancer therapy-induced mucositis: An informative gene network analysis.

    Science.gov (United States)

    Reyes-Gibby, Cielito C; Melkonian, Stephanie C; Wang, Jian; Yu, Robert K; Shelburne, Samuel A; Lu, Charles; Gunn, Gary Brandon; Chambers, Mark S; Hanna, Ehab Y; Yeung, Sai-Ching J; Shete, Sanjay

    2017-01-01

    Mucositis is a complex, dose-limiting toxicity of chemotherapy or radiotherapy that leads to painful mouth ulcers, difficulty eating or swallowing, gastrointestinal distress, and reduced quality of life for patients with cancer. Mucositis is most common for those undergoing high-dose chemotherapy and hematopoietic stem cell transplantation and for those being treated for malignancies of the head and neck. Treatment and management of mucositis remain challenging. It is expected that multiple genes are involved in the formation, severity, and persistence of mucositis. We used Ingenuity Pathway Analysis (IPA), a novel network-based approach that integrates complex intracellular and intercellular interactions involved in diseases, to systematically explore the molecular complexity of mucositis. As a first step, we searched the literature to identify genes that harbor or are close to the genetic variants significantly associated with mucositis. Our literature review identified 27 candidate genes, of which ERCC1, XRCC1, and MTHFR were the most frequently studied for mucositis. On the basis of this 27-gene list, we used IPA to generate gene networks for mucositis. The most biologically significant novel molecules identified through IPA analyses included TP53, CTNNB1, MYC, RB1, P38 MAPK, and EP300. Additionally, uracil degradation II (reductive) and thymine degradation pathways (p = 1.06-08) were most significant. Finally, utilizing 66 SNPs within the 8 most connected IPA-derived candidate molecules, we conducted a genetic association study for oral mucositis in the head and neck cancer patients who were treated using chemotherapy and/or radiation therapy (186 head and neck cancer patients with oral mucositis vs. 699 head and neck cancer patients without oral mucositis). The top ranked gene identified through this association analysis was RB1 (rs2227311, p-value = 0.034, odds ratio = 0.67). In conclusion, gene network analysis identified novel molecules and biological

  14. Identifying novel genes and biological processes relevant to the development of cancer therapy-induced mucositis: An informative gene network analysis.

    Directory of Open Access Journals (Sweden)

    Cielito C Reyes-Gibby

    biological processes, including pathways related to inflammation and oxidative stress, that are relevant to mucositis development, thus providing the basis for future studies to improve the management and treatment of mucositis in patients with cancer.

  15. Intra-individual biological variation in sweat chloride concentrations in CF, CFTR dysfunction, and healthy pediatric subjects.

    Science.gov (United States)

    Cirilli, Natalia; Raia, Valeria; Rocco, Ilaria; De Gregorio, Fabiola; Tosco, Antonella; Salvadori, Laura; Sepe, Angela Ornella; Buzzetti, Roberto; Minicuci, Nadia; Castaldo, Giuseppe

    2018-04-02

    The sweat test is one of the main diagnostic tools used in newborn screening programs and as a confirmatory test, in case of suspect of Cystic Fibrosis (CF). Since sweat chloride (Cl) concentration is also considered an appropriate parameter to explore the efficacy of CFTR modulators in clinical trials, it is crucial to evaluate the biological variability of this test in healthy and pathological conditions. The aim of this pilot study was to determine the intra-individual biological variability of sweat Cl, both in healthy individuals and CF patients and to assess its correlation with diet, season, and menstrual cycle. Thirty-five out of 36 selected subjects (6-18 years) were enrolled by 2 CF care centers and assigned to 3 cohorts: CF, CFTR-related disorder (CFTR-RD) and healthy volunteers. Each participant was subjected to eight sweat tests in different conditions and time of the year. Data were analyzed using linear mixed effects models for repeated measures, taking also into account intra-individual correlations. We observed a high intra-individual variability of sweat Cl, with the lowest mean CV% values among CF patients (20.21 in CF, 29.74 in CFTR-RD, and 31.15 in healthy subjects). Gender and diet had no influence on sweat Cl variability, nor had pubertal age and menstrual phase. Results of this pilot study confirmed that sweat Cl variability is high in CF patients, although non-CF individuals displayed even higher mean CV% values. Season significantly influenced sweat test values only in CF patients, likely due to changes in their hydration status. © 2018 Wiley Periodicals, Inc.

  16. Persistent after-effects of heavy rain on concentrations of ice nuclei and rainfall suggest a biological cause

    Science.gov (United States)

    Bigg, E. K.; Soubeyrand, S.; Morris, C. E.

    2015-03-01

    Rainfall is one of the most important aspects of climate, but the extent to which atmospheric ice nuclei (IN) influence its formation, quantity, frequency, and location is not clear. Microorganisms and other biological particles are released following rainfall and have been shown to serve as efficient IN, in turn impacting cloud and precipitation formation. Here we investigated potential long-term effects of IN on rainfall frequency and quantity. Differences in IN concentrations and rainfall after and before days of large rainfall accumulation (i.e., key days) were calculated for measurements made over the past century in southeastern and southwestern Australia. Cumulative differences in IN concentrations and daily rainfall quantity and frequency as a function of days from a key day demonstrated statistically significant increasing logarithmic trends (R2 > 0.97). Based on observations that cumulative effects of rainfall persisted for about 20 days, we calculated cumulative differences for the entire sequence of key days at each site to create a historical record of how the differences changed with time. Comparison of pre-1960 and post-1960 sequences most commonly showed smaller rainfall totals in the post-1960 sequences, particularly in regions downwind from coal-fired power stations. This led us to explore the hypothesis that the increased leaf surface populations of IN-active bacteria due to rain led to a sustained but slowly diminishing increase in atmospheric concentrations of IN that could potentially initiate or augment rainfall. This hypothesis is supported by previous research showing that leaf surface populations of the ice-nucleating bacterium Pseudomonas syringae increased by orders of magnitude after heavy rain and that microorganisms become airborne during and after rain in a forest ecosystem. At the sites studied in this work, aerosols that could have initiated rain from sources unrelated to previous rainfall events (such as power stations) would

  17. Effect of Organic Solvents and Biologically Relevant Ions on the Light-Induced DNA Cleavage by Pyrene and Its Amino and Hydroxy Derivatives

    Directory of Open Access Journals (Sweden)

    Hongtao Yu

    2002-09-01

    Full Text Available Abstract: Polycyclic aromatic hydrocarbons (PAHs are a class of carcinogenic compounds that are both naturally and artificially produced. Many PAHs are pro-carcinogens that require metabolic activation. Recently, it has been shown that PAH can induce DNA single strand cleavage and formation of PAH-DNA covalent adduct upon irradiation with UVA light. The light-induced DNA cleavage parallels phototoxicity in one instance. The DNA photocleavage efficiency depends on the structure of the PAHs. This article reports the effect of both organic solvents and the presence of biologically relevant ions, Na+, Mg2+, Ca2+, K+, Fe3+, Cu2+, Zn+2, Mn2+, and I-, on the light-induced DNA cleavage by pyrene, 1-hydroxypyrene and 1-aminopyrene. Since both 1-hydroxypyrene (0.6 μM and 1-aminopyrene (6 μM dissolve well in the minimum organic solvents used (2% methanol, dimethylsulfoxide, and dimethylformamide, increasing the amount of the organic solvent resulted in the decrease of the amount of DNA single strand cleavage caused by the combination effect of 1-hydroxy or 1-aminopyrene and UVA light. The result with the less watersoluble pyrene shows that increase of the amount of the organic solvent can increase the amount of DNA single strand DNA photocleavage cause by the combination of pyrene and UVA light. Therefore, there are two effects by the organic solvents: (i to dissolve PAH and (ii to quench DNA photocleavage. The presence of Fe3+ and Zn2+ enhances, while the presence of Ca2+ and Mn2+ inhibits the DNA photocleavage caused by 1-aminopyrene and UVA light. Other metal ions have minimal effect. This means that the effect of ions on DNA photocleavage by PAHs is complex. The presence of KI enhances DNA photocleavage. This indicates that the triplet-excited state of 1-aminopyrene is involved in causing DNA cleavage

  18. Spatial distribution of osteopontin, CD44v6 and podoplanin in the lining epithelium of odontogenic keratocyst, and their biological relevance.

    Science.gov (United States)

    Kechik, Khamisah Awang; Siar, Chong Huat

    2018-02-01

    The odontogenic keratocyst (OKC) remains the most challenging jaw cyst to treat because of its locally-aggressive behaviour and high recurrence potential. Emerging evidence suggests that osteopontin, its receptors CD44v6 and integrin α v , and podoplanin, have a role in the local invasiveness of this cyst. However the spatial distribution characteristics of these pro-invasive markers in the lining epithelium of OKC, and their association with the clinicopathologic parameters of OKC are largely unexplored. This study sought to address these issues in comparison with dentigerous cysts (DCs) and radicular cysts (RCs) and to evaluate their biological relevance. A sample consisting of 20 OKC cases, 10 DCs and 10 RCs was subjected to immunohistochemical staining for osteopontin, CD44v6 and integrin α v , and podoplanin, and semiquantitative analysis was performed. All factors (except integrin α v ) were detected heterogeneously in the constitutive layers of the lining epithelium in all three cyst types. Key observations were significant upregulation of CD44v6 and podoplanin in OKC compared to DCs and RCs, suggesting that these protein molecules may play crucial roles in promoting local invasiveness in OKC (P<0.05). Osteopontin underexpression and distribution patterns were indistinctive among all three cysts indicating its limited role as pro-invasive factor. Clinical parameters showed no significant correlations with all protein factors investigated. Present findings suggest that an osteopontin low CD44v6 high and podoplanin high immunoprofile most probably represent epithelial signatures of OKC and are markers of local invasiveness in this cyst. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Nicotine dose-concentration relationship and pregnancy outcomes in rat: Biologic plausibility and implications for future research

    International Nuclear Information System (INIS)

    Hussein, Jabeen; Farkas, Svetlana; MacKinnon, Yolanda; Ariano, Robert E.; Sitar, Daniel S.; Hasan, Shabih U.

    2007-01-01

    Cigarette smoke (CS) exposure during pregnancy can lead to profound adverse effects on fetal development. Although CS contains several thousand chemicals, nicotine has been widely used as its surrogate as well as in its own right as a neuroteratogen. The justification for the route and dose of nicotine administration is largely based on inferential data suggesting that nicotine 6 mg/kg/day infused continuously via osmotic mini pumps (OMP) would mimic maternal CS exposure. We provide evidence that 6 mg/kg/day nicotine dose as commonly administered to pregnant rats leads to plasma nicotine concentrations that are 3-10-fold higher than those observed in moderate to heavy smokers and pregnant mothers, respectively. Furthermore, the cumulative daily nicotine dose exceeds by several hundred fold the amount consumed by human heavy smokers. Our study does not support the widely accepted notion that regardless of the nicotine dose, a linear nicotine dose-concentration relationship exists in a steady-state OMP model. We also show that total nicotine clearance increases with advancing pregnancy but no significant change is observed between the 2nd and 3rd trimester. Furthermore, nicotine infusion even at this extremely high dose has little effect on a number of maternal and fetal biologic variables and pregnancy outcome suggesting that CS constituents other than nicotine mediate the fetal growth restriction in infants born to smoking mothers. Our current study has major implications for translational research in developmental toxicology and pharmacotherapy using nicotine replacement treatment as an aid to cessation of cigarette smoking in pregnant mothers

  20. Raman spectroscopy for the evaluation of the effects of different concentrations of Copper on the chemical composition and biological activity of basil essential oil

    Science.gov (United States)

    Nawaz, Haq; Hanif, Muhammad Asif; Ayub, Muhammad Adnan; Ishtiaq, Faiqa; Kanwal, Nazish; Rashid, Nosheen; Saleem, Muhammad; Ahmad, Mushtaq

    2017-10-01

    The present study is performed to evaluate the effect of different concentrations of Cu as fertilizer on the chemical composition of basil essential oil and its biological activity including antioxidant and antifungal activities by employing Raman spectroscopy. Moreover, the effect of Cu is also determined on the vegetative growth and essential oil yield. Both, antifungal and antioxidant activities were found to be maximum with essential oils obtained at 0.04 mg/l concentration of Cu fertilizer. The results of the GC-MS and Raman spectroscopy have revealed that the linalool and estragole are found to be as a major chemical compound in basil essential oil. The Raman spectral changes associated with these biological components lead to the conclusion that estragole seems to have dominating effect in the biological activities of the basil essential oil as compared to linalool although the latter is observed in greater concentration.

  1. Clinical relevance of the discrepancy in phenylalanine concentrations analyzed using tandem mass spectrometry compared with ion-exchange chromatography in phenylketonuria

    Directory of Open Access Journals (Sweden)

    Bridget M. Stroup

    2016-03-01

    Conclusion: Use of DBS analyzed using MS/MS to monitor blood phe concentrations in individuals with PKU yields significantly lower phe levels compared to plasma phe levels analyzed using IEC. Optimization of current testing methodologies for measuring phe in DBS, along with patient education regarding the appropriate technique for spotting blood on filter paper is needed to improve the accuracy of using DBS to measure phe concentrations in PKU management.

  2. Analysis of Blood Concentrations of Zinc, Germanium, and Lead and Relevant Environmental Factors in a Population Sample from Shandong Province, China

    Directory of Open Access Journals (Sweden)

    Long Li

    2017-02-01

    Full Text Available Trace elements, including zinc (Zn and germanium (Ge, are essential for health; deficiency or excess levels of trace elements results is harmful. As a result of industrial and agricultural production, Pb widely exists in people’s living environment. It is absorbed mainly through the respiratory and digestive tracts, producing systemic harm. Reference values for a normal, healthy population are necessary for health assessment, prevention and treatment of related diseases, and evaluation of occupational exposures. Reference ranges for the Chinese population have not been established. From March 2009 to February 2010; we collected data and blood samples (n = 1302 from residents aged 6–60 years living in Shandong Province, China. We measured blood concentrations of Zn, Ge, and Pb using inductively coupled plasma mass spectrometry to determine reference ranges. Results were stratified by factors likely to affect the concentrations of these trace elements: sex, use of cosmetics or hair dye, age, alcohol intake, smoking habits, and consumption of fried food. The overall geometric mean (GM concentrations (95% confidence interval were 3.14 (3.08–3.20 mg/L for Zn, 19.9 (19.3–20.6 μg/L for Ge, and 24.1 (23.2–25.1 μg/L for Pb. Blood Zn concentrations were higher in women than in men (p < 0.001, while the opposite was found for Pb (p < 0.001 and sex did not influence Ge (p = 0.095. Alcohol use was associated with higher blood concentrations of Zn (p = 0.002, Ge (p = 0.002, and Pb (p = 0.001. The GM concentration of Zn was highest in 20–30-year-olds (p < 0.001, while Pb concentrations were highest in 12–16-year-olds (p < 0.001. Use of hair dye was associated with lower blood concentrations of Ge (p < 0.05. GM blood concentrations of Pb differed significantly between those who consumed fried foods 1–2 times/month (18.7 μg/L, 1–2 times/week (20.9 μg/L, and every day (28.5 μg/L; p < 0.001. Blood Pb concentrations were higher in subjects

  3. Environmentally relevant pyrethroid mixtures: A study on the correlation of blood and brain concentrations of a mixture of pyrethroid insecticides to motor activity in the rat.

    Science.gov (United States)

    Hughes, Michael F; Ross, David G; Starr, James M; Scollon, Edward J; Wolansky, Marcelo J; Crofton, Kevin M; DeVito, Michael J

    2016-06-01

    Human exposure to multiple pyrethroid insecticides may occur because of their broad use on crops and for residential pest control. To address the potential health risk from co-exposure to pyrethroids, it is important to understand their disposition and toxicity in target organs such as the brain, and surrogates such as the blood when administered as a mixture. The objective of this study was to assess the correlation between blood and brain concentrations of pyrethroids and neurobehavioral effects in the rat following an acute oral administration of the pyrethroids as a mixture. Male Long-Evans rats were administered a mixture of β-cyfluthrin, cypermethrin, deltamethrin, esfenvalerate and cis- and trans-permethrin in corn oil at seven dose levels. The pyrethroid with the highest percentage in the dosing solution was trans-permethrin (31% of total mixture dose) while deltamethrin and esfenvalerate had the lowest percentage (3%). Motor activity of the rats was then monitored for 1h. At 3.5h post-dosing, the animals were euthanized and blood and brain were collected. These tissues were extracted and analyzed for parent pyrethroid using HPLC-tandem mass spectrometry. Cypermethrin and cis-permethrin were the predominate pyrethroids detected in blood and brain, respectively, at all dosage levels. The relationship of total pyrethroid concentration between blood and brain was linear (r=0.93). The pyrethroids with the lowest fraction in blood were trans-permethrin and β-cyfluthrin and in brain were deltamethrin and esfenvalerate. The relationship between motor activity of the treated rats and summed pyrethroid blood and brain concentration was described using a sigmoidal Emax model with the Effective Concentration50 being more sensitive for brain than blood. The data suggests summed pyrethroid rat blood concentration could be used as a surrogate for brain concentration as an aid to study the neurotoxic effects of pyrethroids administered as a mixture under the conditions

  4. The dynamic ocean biological pump: Insights from a global compilation of particulate organic carbon, CaCO3, and opal concentration profiles from the mesopelagic

    Science.gov (United States)

    Lam, Phoebe J.; Doney, Scott C.; Bishop, James K. B.

    2011-09-01

    We have compiled a global data set of 62 open ocean profiles of particulate organic carbon (POC), CaCO3, and opal concentrations collected by large volume in situ filtration in the upper 1000 m over the last 30 years. We define concentration-based metrics for the strength (POC concentration at depth) and efficiency (attenuation of POC with depth in the mesopelagic) of the biological pump. We show that the strength and efficiency of the biological pump are dynamic and are characterized by a regime of constant and high transfer efficiency at low to moderate surface POC and a bloom regime where the height of the bloom is characterized by a weak deep biological pump and low transfer efficiency. The variability in POC attenuation length scale manifests in a clear decoupling between the strength of the shallow biological pump (e.g., POC at the export depth) and the strength of the deep biological pump (POC at 500 m). We suggest that the paradigm of diatom-driven export production is driven by a too restrictive perspective on upper mesopelagic dynamics. Indeed, our full mesopelagic analysis suggests that large, blooming diatoms have low transfer efficiency and thus may not export substantially to depth; rather, our analysis suggests that ecosystems characterized by smaller cells and moderately high %CaCO3 have a high mesopelagic transfer efficiency and can have higher POC concentrations in the deep mesopelagic even with relatively low surface or near-surface POC. This has negative implications for the carbon sequestration prospects of deliberate iron fertilization.

  5. Gas-phase naphthalene concentration data recovery in ambient air and its relevance as a tracer of sources of volatile organic compounds

    Science.gov (United States)

    Uria-Tellaetxe, Iratxe; Navazo, Marino; de Blas, Maite; Durana, Nieves; Alonso, Lucio; Iza, Jon

    2016-04-01

    Despite the toxicity of naphthalene and the fact that it is a precursor of atmospheric photooxidants and secondary aerosol, studies on ambient gas-phase naphthalene are generally scarce. Moreover, as far as we are concerned, this is the first published one using long-term hourly ambient gas-phase naphthalene concentrations. In this work, it has been also demonstrated the usefulness of ambient gas-phase naphthalene to identify major sources of volatile organic compounds (VOC) in complex scenarios. Initially, in order to identify main benzene emission sources, hourly ambient measurements of 60 VOC were taken during a complete year together with meteorological data in an urban/industrial area. Later, due to the observed co-linearity of some of the emissions, a procedure was developed to recover naphthalene concentration data from recorded chromatograms to use it as a tracer of the combustion and distillation of petroleum products. The characteristic retention time of this compound was determined comparing previous GC-MS and GC-FID simultaneous analysis by means of relative retention times, and its concentration was calculated by using relative response factors. The obtained naphthalene concentrations correlated fairly well with ethene (r = 0.86) and benzene (r = 0.92). Besides, the analysis of daily time series showed that these compounds followed a similar pattern, very different from that of other VOC, with minimum concentrations at day-time. This, together with the results from the assessment of the meteorological dependence pointed out a coke oven as the major naphthalene and benzene emitting sources in the study area.

  6. An alkaline comet assay study on the antimalarial drug atovaquone in human peripheral blood lymphocytes: a study based on clinically relevant concentrations.

    Science.gov (United States)

    Dinter, Domagoj; Gajski, Goran; Garaj-Vrhovac, Vera

    2013-01-01

    Atovaquone, a hydroxynaphthoquinone, is an anti-parasite drug, selectively targeting the mitochondrial respiratory chain of malaria parasite. It is used for both the treatment and prevention of malaria, usually in a fixed combination with proguanil. Although atovaquone has not often been associated with severe adverse reactions in the recommended dosages and has a relatively favorable side effect profile, the present study was undertaken to evaluate its cytogenotoxic potential towards human peripheral blood lymphocytes. Two different concentrations of atovaquone found in plasma when used in fixed-dose combination with proguanile hydrochloride were used with and without S9 metabolic activation: 2950 ng ml(-1) used for prophylactic treatment and 11 800 ng ml(-1) used in treatment of malaria. The results showed that lymphocyte viability was not affected after the treatment, suggesting that atovaquone was not cytotoxic in the given concentrations. With the alkaline comet assay we demonstrated that in human peripheral blood lymphocytes no significant changes in comet parameters occurred after the treatment. There were no differences in tested parameters with the addition of S9 metabolic activation, indicating that atovaquone either has no metabolite or it is not toxic in the given concentrations. Since no effects were observed after the treatment, it is to be concluded that atovaquone is safe from the aspect of genototoxicity in the recommended dosages. Copyright © 2011 John Wiley & Sons, Ltd.

  7. Accelerator mass spectrometry analysis of 14C-oxaliplatin concentrations in biological samples and 14C contents in biological samples and antineoplastic agents

    Science.gov (United States)

    Toyoguchi, Teiko; Kobayashi, Takeshi; Konno, Noboru; Shiraishi, Tadashi; Kato, Kazuhiro; Tokanai, Fuyuki

    2015-10-01

    Accelerator mass spectrometry (AMS) is expected to play an important role in microdose trials. In this study, we measured the 14C concentration in 14C-oxaliplatin-spiked serum, urine and supernatant of fecal homogenate samples in our Yamagata University (YU) - AMS system. The calibration curves of 14C concentration in serum, urine and supernatant of fecal homogenate were linear (the correlation coefficients were ⩾0.9893), and the precision and accuracy was within the acceptance criteria. To examine a 14C content of water in three vacuum blood collection tubes and a syringe were measured. 14C was not detected from water in these devices. The mean 14C content in urine samples of 6 healthy Japanese volunteers was 0.144 dpm/mL, and the intra-day fluctuation of 14C content in urine from a volunteer was little. The antineoplastic agents are administered to the patients in combination. Then, 14C contents of the antineoplastic agents were quantitated. 14C contents were different among 10 antineoplastic agents; 14C contents of paclitaxel injection and docetaxel hydrate injection were higher than those of the other injections. These results indicate that our quantitation method using YU-AMS system is suited for microdosing studies and that measurement of baseline and co-administered drugs might be necessary for the studies in low concentrations.

  8. Accelerator mass spectrometry analysis of "1"4C-oxaliplatin concentrations in biological samples and "1"4C contents in biological samples and antineoplastic agents

    International Nuclear Information System (INIS)

    Toyoguchi, Teiko; Kobayashi, Takeshi; Konno, Noboru; Shiraishi, Tadashi; Kato, Kazuhiro; Tokanai, Fuyuki

    2015-01-01

    Accelerator mass spectrometry (AMS) is expected to play an important role in microdose trials. In this study, we measured the "1"4C concentration in "1"4C-oxaliplatin-spiked serum, urine and supernatant of fecal homogenate samples in our Yamagata University (YU) – AMS system. The calibration curves of "1"4C concentration in serum, urine and supernatant of fecal homogenate were linear (the correlation coefficients were ⩾0.9893), and the precision and accuracy was within the acceptance criteria. To examine a "1"4C content of water in three vacuum blood collection tubes and a syringe were measured. "1"4C was not detected from water in these devices. The mean "1"4C content in urine samples of 6 healthy Japanese volunteers was 0.144 dpm/mL, and the intra-day fluctuation of "1"4C content in urine from a volunteer was little. The antineoplastic agents are administered to the patients in combination. Then, "1"4C contents of the antineoplastic agents were quantitated. "1"4C contents were different among 10 antineoplastic agents; "1"4C contents of paclitaxel injection and docetaxel hydrate injection were higher than those of the other injections. These results indicate that our quantitation method using YU-AMS system is suited for microdosing studies and that measurement of baseline and co-administered drugs might be necessary for the studies in low concentrations.

  9. Accelerator mass spectrometry analysis of {sup 14}C-oxaliplatin concentrations in biological samples and {sup 14}C contents in biological samples and antineoplastic agents

    Energy Technology Data Exchange (ETDEWEB)

    Toyoguchi, Teiko, E-mail: tteiko@med.id.yamagata-u.ac.jp [Department of Pharmacy, Yamagata University Hospital, 2-2-2 Iida-Nishi, Yamagata-shi, Yamagata 990-9585 (Japan); Kobayashi, Takeshi; Konno, Noboru; Shiraishi, Tadashi [Department of Pharmacy, Yamagata University Hospital, 2-2-2 Iida-Nishi, Yamagata-shi, Yamagata 990-9585 (Japan); Kato, Kazuhiro; Tokanai, Fuyuki [Department of Physics, Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata-shi, Yamagata 990-8560 (Japan)

    2015-10-15

    Accelerator mass spectrometry (AMS) is expected to play an important role in microdose trials. In this study, we measured the {sup 14}C concentration in {sup 14}C-oxaliplatin-spiked serum, urine and supernatant of fecal homogenate samples in our Yamagata University (YU) – AMS system. The calibration curves of {sup 14}C concentration in serum, urine and supernatant of fecal homogenate were linear (the correlation coefficients were ⩾0.9893), and the precision and accuracy was within the acceptance criteria. To examine a {sup 14}C content of water in three vacuum blood collection tubes and a syringe were measured. {sup 14}C was not detected from water in these devices. The mean {sup 14}C content in urine samples of 6 healthy Japanese volunteers was 0.144 dpm/mL, and the intra-day fluctuation of {sup 14}C content in urine from a volunteer was little. The antineoplastic agents are administered to the patients in combination. Then, {sup 14}C contents of the antineoplastic agents were quantitated. {sup 14}C contents were different among 10 antineoplastic agents; {sup 14}C contents of paclitaxel injection and docetaxel hydrate injection were higher than those of the other injections. These results indicate that our quantitation method using YU-AMS system is suited for microdosing studies and that measurement of baseline and co-administered drugs might be necessary for the studies in low concentrations.

  10. Twenty years of biological monitoring of element concentrations in permanent forest and grassland plots in Baden-Württemberg (SW Germany).

    Science.gov (United States)

    Franzaring, Jürgen; Holz, Ingo; Zipperle, Jürgen; Fangmeier, Andreas

    2010-01-01

    nutrients C, N, S, P, Ca, K and Mg and the metals Mn, Cd, Pb, Al, Cu, Ni and Hg. Data were analysed using descriptive and multivariate statistics and maps were produced to identify regional differences in pollutant deposition. Out of the elements analysed, lead and sulphur concentrations showed the most pronounced downward trends over time in tree foliage and grassland samples with the largest decreases observed in the early 1990 s. Both the reduced lead and sulphur levels in the biomonitors reflect the successful implementation of clean air policies, i.e. the introduction of unleaded gasoline, the availability of desulphurisation technologies and the economic transition of Eastern European heavy industries. However, the decrease in sulphur concentrations was lower in beech foliage from SW Germany as compared to beech leaves from six German national parks suggesting regional differences in sulphur deposition and trends thereof. At the same time, sulphur concentrations declined more strongly in the grassland samples indicating that much of the deposited sulphur remains in the forest ecosystems while in the grassland ecosystems it is gradually removed by the frequent cutting and grazing. During the time series, the decrease in sulphur deposition coincided with a marked increase in rain pH. At the same time, the increasing nitrogen concentrations observed over time in beech leaves suggest that emissions of oxidised and reduced nitrogen are still adding to the large-scale eutrophication of SW German forests. However, N concentrations in both the tree foliage and in the bulk grassland samples were unrelated to the modelled N deposition. When also considering macronutrient concentrations and N:P and N:K ratios, the results point to serious nutrient imbalances in many beech forests, which may reduce plant vitality and tree growth in the long run. Biological monitoring using plants is an effective tool to address changes in the environmental quality over time and space. The success

  11. Concentrations of polybrominated diphenyl ethers (PBDEs) in central air-conditioner filter dust and relevance of non-dietary exposure in occupational indoor environments in Greece

    International Nuclear Information System (INIS)

    Besis, Athanasios; Katsoyiannis, Athanasios; Botsaropoulou, Elisavet; Samara, Constantini

    2014-01-01

    Polybrominated Diphenyl Ethers (PBDEs) are ubiquitous in the indoor environment owing to their use in consumer products and various studies around the world have found higher concentrations indoors than outdoors. Central air conditioner (A/C) systems have been widely used in many workplaces, therefore, studying of PBDEs in central A/C filter dust is useful to better understand the occurrences and health implications of PBDEs in indoor environments. The present study examined the occurrence of PBDEs in central A/C filter dust collected from various workplaces (n = 20) in Thessaloniki, Greece. The sum concentrations of 21 target congeners (∑ 21 PBDE) in A/C dust ranged between 84 and 4062 ng g −1 with a median value of 1092 ng g −1 , while BDE-209 was found to be the most abundant BDE congener. The daily intake via dust ingestion of PBDEs estimated for the employees of the occupational settings ranged from 3 to 45 ng day −1 (median 12 ng day −1 ). - Highlights: • PBDEs were investigated in dust of A/C filters in occupational settings in Thessaloniki, Greece. • BDE-209 was found to be the most abundant BDE congener. • High levels of PBDEs were found in a newspaper building, internet cafes and electronic shops. • PBDEs were attributable to the extensive presence and/or usage of electronic devices. • Exposure of employees to PBDEs via indoor dust ingestion was estimated at 12 ng day −1 . - PBDEs were for the first time measured in dust from central A/C filters in workplaces of Greece and their concentrations were used to estimate the non-dietary human exposure

  12. At clinically relevant concentrations the anaesthetic/amnesic thiopental but not the anticonvulsant phenobarbital interferes with hippocampal sharp wave-ripple complexes

    Science.gov (United States)

    Papatheodoropoulos, Costas; Sotiriou, Evangelos; Kotzadimitriou, Dimitrios; Drimala, Panagiota

    2007-01-01

    Background Many sedative agents, including anesthetics, produce explicit memory impairment by largely unknown mechanisms. Sharp-wave ripple (SPW-R) complexes are network activity thought to represent the neuronal substrate for information transfer from the hippocampal to neocortical circuits, contributing to the explicit memory consolidation. In this study we examined and compared the actions of two barbiturates with distinct amnesic actions, the general anesthetic thiopental and the anticonvulsant phenobarbital, on in vitro SPW-R activity. Results Using an in vitro model of SPW-R activity we found that thiopental (50–200 μM) significantly and concentration-dependently reduced the incidence of SPW-R events (it increased the inter-event period by 70–430 %). At the concentration of 25 μM, which clinically produces mild sedation and explicit memory impairment, thiopental significantly reduced the quantity of ripple oscillation (it reduced the number of ripples and the duration of ripple episodes by 20 ± 5%, n = 12, P Phenobarbital significantly accelerated SPWs at 50 and 100 μM whereas it reduced their rate at 200 and 400 μM. Furthermore, it significantly prolonged SPWs, reduced their synchrony and reduced the quantity of ripples only at the clinically very high concentration of 400 μM, reported to affect memory. Conclusion We hypothesize that thiopental, by interfering with SPW-R activity, through enhancement of the GABAA receptor-mediated transmission, affects memory processes which involve hippocampal circuit activation. The quantity but not the frequency of ripple oscillation was affected by the drug. PMID:17672909

  13. Concentrations of polybrominated diphenyl ethers (PBDEs) in central air-conditioner filter dust and relevance of non-dietary exposure in occupational indoor environments in Greece.

    Science.gov (United States)

    Besis, Athanasios; Katsoyiannis, Athanasios; Botsaropoulou, Elisavet; Samara, Constantini

    2014-05-01

    Polybrominated Diphenyl Ethers (PBDEs) are ubiquitous in the indoor environment owing to their use in consumer products and various studies around the world have found higher concentrations indoors than outdoors. Central air conditioner (A/C) systems have been widely used in many workplaces, therefore, studying of PBDEs in central A/C filter dust is useful to better understand the occurrences and health implications of PBDEs in indoor environments. The present study examined the occurrence of PBDEs in central A/C filter dust collected from various workplaces (n = 20) in Thessaloniki, Greece. The sum concentrations of 21 target congeners (∑21PBDE) in A/C dust ranged between 84 and 4062 ng g(-1) with a median value of 1092 ng g(-1), while BDE-209 was found to be the most abundant BDE congener. The daily intake via dust ingestion of PBDEs estimated for the employees of the occupational settings ranged from 3 to 45 ng day(-1) (median 12 ng day(-1)). Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Telecommunication Support System Using Keywords and Their Relevant Information in Videoconferencing — Presentation Method for Keeping Audience's Concentration at Distance Lectures

    Science.gov (United States)

    Asai, Kikuo; Kondo, Kimio; Kobayashi, Hideaki; Saito, Fumihiko

    We developed a prototype system to support telecommunication by using keywords selected by the speaker in a videoconference. In the traditional presentation style, a speaker talks and uses audiovisual materials, and the audience at remote sites looks at these materials. Unfortunately, the audience often loses concentration and attention during the talk. To overcome this problem, we investigate a keyword presentation style, in which the speaker holds keyword cards that enable the audience to see additional information. Although keyword captions were originally intended for use in video materials for learning foreign languages, they can also be used to improve the quality of distance lectures in videoconferences. Our prototype system recognizes printed keywords in a video image at a server, and transfers the data to clients as multimedia functions such as language translation, three-dimensional (3D) model visualization, and audio reproduction. The additional information is collocated to the keyword cards in the display window, thus forming a spatial relationship between them. We conducted an experiment to investigate the properties of the keyword presentation style for an audience. The results suggest the potential of the keyword presentation style for improving the audience's concentration and attention in distance lectures by providing an environment that facilitates eye contact during videoconferencing.

  15. At clinically relevant concentrations the anaesthetic/amnesic thiopental but not the anticonvulsant phenobarbital interferes with hippocampal sharp wave-ripple complexes

    Directory of Open Access Journals (Sweden)

    Sotiriou Evangelos

    2007-07-01

    Full Text Available Abstract Background Many sedative agents, including anesthetics, produce explicit memory impairment by largely unknown mechanisms. Sharp-wave ripple (SPW-R complexes are network activity thought to represent the neuronal substrate for information transfer from the hippocampal to neocortical circuits, contributing to the explicit memory consolidation. In this study we examined and compared the actions of two barbiturates with distinct amnesic actions, the general anesthetic thiopental and the anticonvulsant phenobarbital, on in vitro SPW-R activity. Results Using an in vitro model of SPW-R activity we found that thiopental (50–200 μM significantly and concentration-dependently reduced the incidence of SPW-R events (it increased the inter-event period by 70–430 %. At the concentration of 25 μM, which clinically produces mild sedation and explicit memory impairment, thiopental significantly reduced the quantity of ripple oscillation (it reduced the number of ripples and the duration of ripple episodes by 20 ± 5%, n = 12, P P P Conclusion We hypothesize that thiopental, by interfering with SPW-R activity, through enhancement of the GABAA receptor-mediated transmission, affects memory processes which involve hippocampal circuit activation. The quantity but not the frequency of ripple oscillation was affected by the drug.

  16. Perfluoroalkylsulfonic and carboxylic acids in earthworms (Eisenia fetida): Accumulation and effects results from spiked soils at PFAS concentrations bracketing environmental relevance.

    Science.gov (United States)

    Karnjanapiboonwong, Adcharee; Deb, Sanjit K; Subbiah, Seenivasan; Wang, Degeng; Anderson, Todd A

    2018-05-01

    Effects of perfluorobutanesulfonic acid (PFBS), perfluorohexanesulfonic acid (PFHxS), perfluorononanoic acid (PFNA), and perfluoroheptanoic acid (PFHpA) on earthworms (Eisenia fetida) in soils contaminated with these compounds at 0.1, 1, 10, 1,000, and 100,000 μg kg -1 dry weight, covering concentration levels found in background, biosolid-amended, and facility-surrounding soils, were investigated. Earthworms were exposed to spiked soil for 21 days. Concentrations of these compounds in earthworms after 21-d exposure ranged from below detection to 127 mg kg -1 wet weight with the rank order of PFNA > PFHxS > PFHpA > PFBS; no mortality of earthworms was observed in all treatments including controls, except PFBS at 1,000 μg kg -1 and all PFASs at 100,000 μg kg -1 . The highest weight loss (29%) was observed for earthworms exposed to PFNA at 100,000 μg kg -1 , which was significantly different from all other treatments except PFHpA at 100,000 μg kg -1 . These results are expected to fill some data gaps in toxicity of PFASs in terrestrial environments and provide helpful information on the potential for trophic transport of PFASs from soil to higher organisms. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Immunolocalisation of members of the polypeptide N-acetylgalactosaminyl transferase (ppGalNAc-T) family is consistent with biologically relevant altered cell surface glycosylation in breast cancer

    DEFF Research Database (Denmark)

    Brooks, Susan A; Carter, Tracey M; Bennett, Eric P

    2007-01-01

    understood, may mediate the synthesis of varied glycoforms of cellular proteins with different biological activities. Disruptions in glycosylation are a common feature of cancer and may have functional significance. Immunocytochemistry with confocal scanning laser microscopy was employed to detect members...... of the ppGalNAc-T family, ppGalNAc-T1, -T2, -T3, -T4 and -T6 in a range of breast cell lines. The cells were chosen to represent a range of phenotypes from 'normal'/benign (HMT 3,522), primary, non-metastatic breast cancer (BT 474), to aggressive, metastatic breast cancer (ZR75-1, T47D, MCF-7, DU 4...... tightly restricted ppGalNAc-T's may result in initiation of O-linked glycosylation at normally unoccupied potential glycosylation sites leading to altered glycoforms of proteins with changed biological activity which may contribute to the pathogenesis of cancer....

  18. Measurement of neutrons emitted following the absorption of stopped negative pions in the biologically relevant nuclei 12C, 14N und 16O

    International Nuclear Information System (INIS)

    Klein, U.

    1978-05-01

    A time-of-flight technique has been used to measure the energy spectra of neutrons emitted following the absorption of stopped negative pions in the biologically interesting light out at the biomedical pion channel πE3 of the Swiss Institute of Nuclear Research (SIN). The neutron spectra for all the target nuclei studied are the same within the error bars. The spectra are characterized by a low-energy 'evaporation' part and a high-energy 'direct' component. (orig.) [de

  19. Effects of an environmentally relevant concentration of diuron on oyster genitors during gametogenesis: responses of early molecular and cellular markers and physiological impacts.

    Science.gov (United States)

    Akcha, F; Barranger, A; Bachère, E; Berthelin, C Heude; Piquemal, D; Alonso, P; Sallan, R Rondon; Dimastrogiovanni, G; Porte, C; Menard, D; Szczybelski, A; Benabdelmouna, A; Auffret, M; Rouxel, J; Burgeot, T

    2016-04-01

    Genitors of the Pacific oyster Crassostrea gigas were submitted during gametogenesis to a short pulse exposure to the herbicide diuron at a realistic environmental concentration. Histological analysis showed no effect of diuron on gametogenesis course, sex ratio and reproductive effort. A non-significant increase in testosterone and progesterone levels was observed in genitors exposed to the herbicide. At cell level, diuron exposure was shown to modulate the phagocytic activity of circulating hemocytes. The results of a transcriptional analysis showed that diuron affected the expression of genes belonging to functions known to play a major role during oyster gametogenesis such as gene transcription regulation, DNA replication and repair, DNA methylation and cytokinesis. Taking into account the results we previously obtained on the same genitors, this study showed a negative effect of diuron on oyster reproduction by inducing both structural and functional modifications of the DNA.

  20. Cytogenetic and oxidative status of human lymphocytes after exposure to clinically relevant concentrations of antimalarial drugs atovaquone and proguanil hydrochloride in vitro.

    Science.gov (United States)

    Dinter, Domagoj; Gajski, Goran; Domijan, Ana-Marija; Garaj-Vrhovac, Vera

    2015-12-01

    Atovaquone (ATO) and proguanil hydrochloride (PROG) is the fixed combination for the prevention and treatment of Plasmodium falciparum malaria. As safe and effective antimalarial drugs are needed in both the treatment and the prophylaxis of malaria, this study was performed to investigate their possible cyto/genotoxic potential towards human lymphocytes and the possible mechanism responsible for it. Two different concentrations of ATO and PROG were used with and without S9 metabolic activation. The concentrations used were those found in human plasma when a fixed-dose combination of ATO and PROG was used: 2950/130 ng/mL after prophylactic treatment and 11 800/520 ng/mL after treatment of malaria, respectively. Possible cellular and DNA-damaging effects were evaluated by cell viability and alkaline comet assays, while oxidative stress potential was evaluated by formamidopyrimidine-DNA glycosylase (Fpg)-modified comet assay, in addition to measuring malondialdehyde and glutathione levels. According to our results, the ATO/PROG combination displayed only weak cyto/genotoxic potential towards human lymphocytes with no impact on oxidative stress parameters, suggesting that oxidative stress is not implicated in their mechanism of action towards human lymphocytes. Given that the key portion of the damaging effects was induced after S9 metabolic activation, it is to presume that the principal metabolite of PROG, cycloguanil, had the greatest impact. The obtained results indicate that the ATO/PROG combination is relatively safe for the consumption from the aspect of cyto/genotoxicity, especially if used for prophylactic treatment. Nevertheless, further cytogenetic research and regular patient monitoring are needed to minimize the risk of adverse events especially among frequent travellers. © 2015 Société Française de Pharmacologie et de Thérapeutique.

  1. Biological removal of sulfur from coal flotation concentrate by culture isolated from coal washery plant tailing dump

    Energy Technology Data Exchange (ETDEWEB)

    Jorjani, E. [Azad University, Tehran (Iran). Mining Engineering Dept.

    2005-10-15

    A combination of flotation and microbial leaching processes was used to achieve acceptable level of sulfur and ash in Tabas coal sample of Iran. Representative sample of the minus 500 micron size fraction was subjected to flotation separation for the removal of ash and sulfur. The final concentrate with recovery, combustion value and sulfur content of 86.03, 86.45 and 1.35% respectively was achieved at pH 8 and following reagent dosage and operating conditions: collector: diesel oil (1200 g/ton), frother: MIBC (5%) + pine oil (95%) with concentration of 120 (g/ton), depressant: sodium silicate (1000 g/ton), particle size: {lt} 500 {mu} m and pulp density: 7%. Because of fine distribution of sulfur on Tabas coal macerals and lithotypes, high percentage of total sulfur (79.9%) is distributed in flotation concentrate and only 20.1% is yielded in the tails. So microbial leaching using a species isolated from coal washery plant tailing dump was used in batch system to remove sulfur from flotation concentrate. The conditions were optimized for the maximum removal of sulfur. These conditions were found to be pH of 2, particle size less than 0.18 mm; pulp density: 8%, temperature: 30 {sup o}C, shaking rate: 150 rpm conditions. Total sulfur and ash content was reduced by bioleaching from 13.55 and 1.35 in flotation concentrate to 9.47 and 0.55 in the final leached concentrate, a reduction of 35 and 61.9% respectively. Sterilization of coal adversely affects the sulfur reduction. The results suggest that the isolated culture is sufficiently effective for depyritization of Tabas coal flotation concentrate in stirred system.

  2. Molecular environment of stable iodine and radioiodine (129I) in natural organic matter: Evidence inferred from NMR and binding experiments at environmentally relevant concentrations

    Science.gov (United States)

    Xu, Chen; Zhong, Junyan; Hatcher, Patrick G.; Zhang, Saijin; Li, Hsiu-Ping; Ho, Yi-Fang; Schwehr, Kathleen A.; Kaplan, Daniel I.; Roberts, Kimberly A.; Brinkmeyer, Robin; Yeager, Chris M.; Santschi, Peter H.

    2012-11-01

    129I is a major by-product of nuclear fission and had become one of the major radiation risk drivers at Department of Energy (DOE) sites. 129I is present at elevated levels in the surface soils of the Savannah River Site (SRS) F-Area and was found to be bound predominantly to soil organic matter (SOM). Naturally bound 127I and 129I to sequentially extracted humic acids (HAs), fulvic acids (FAs) and a water extractable colloid (WEC) were measured in a 129I-contaminated wetland surface soil located on the SRS. WEC is a predominantly colloidal organic fraction obtained from soil re-suspension experiments to mimic the fraction that may be released during groundwater exfiltration, storm water or surface runoff events. For the first time, NMR techniques were applied to infer the molecular environment of naturally occurring stable iodine and radioiodine binding to SOM. Iodine uptake partitioning coefficients (Kd) by these SOM samples at ambient iodine concentrations were also measured and related to quantitative structural analyses by 13C DPMAS NMR and solution state 1H NMR on the eight humic acid fractions. By assessing the molecular environment of iodine, it was found that it was closely associated with the aromatic regions containing esterified products of phenolic and formic acids or other aliphatic carboxylic acids, amide functionalities, quinone-like structures activated by electron-donating groups (e.g., NH2), or a hemicellulose-lignin-like complex with phenyl-glycosidic linkages. However, FAs and WEC contained much greater concentrations of 127I or 129I than HAs. The contrasting radioiodine contents among the three different types of SOM (HAs, FAs and WEC) suggest that the iodine binding environment cannot be explained solely by the difference in the amount of their reactive binding sites. Instead, indirect evidence indicates that the macro-molecular conformation, such as the hydrophobic aliphatic periphery hindering the active aromatic cores and the hydrophilic

  3. Long-term exposure to gold nanoparticles accelerates larval metamorphosis without affecting mass in wood frogs (Lithobates sylvaticus) at environmentally relevant concentrations.

    Science.gov (United States)

    Fong, Peter P; Thompson, Lucas B; Carfagno, Gerardo L F; Sitton, Andrea J

    2016-09-01

    Nanoparticles are environmental contaminants of emerging concern. Exposure to engineered nanoparticles has been shown to have detrimental effects on aquatic organisms. The authors synthesized gold nanoparticles (18.1 ± 3.5 nm) and tested their effects on time to and weight at metamorphosis in wood frog (Lithobates sylvaticus) tadpoles, a species known to be sensitive to environmental stressors. Continuous exposure to all concentrations of gold nanoparticles (0.05 pM, 0.5 pM, and 5 pM in particles) for up to 55 d significantly reduced time to metamorphosis by as much as an average of 3 d (p metamorphosis. The approximately 18-nm gold nanoparticles used were metastable in dechlorinated tap water, resulting in a change in surface charge and aggregation over time, leading to negatively charged aggregates that were on the order of 60 nm to 110 nm. Nanoparticle aggregation could exacerbate the effect on time to metamorphosis. To the authors' knowledge, the present study is the first report on the effect of engineered nanoparticles of any kind on life-history variables in an amphibian, a taxonomic group that has been declining globally for at least 25 yr. Environ Toxicol Chem 2016;35:2304-2310. © 2016 SETAC. © 2016 SETAC.

  4. Biological variables and health status affecting inorganic element concentrations in harbour porpoises (Phocoena phocoena) from Portugal (western Iberian Peninsula)

    International Nuclear Information System (INIS)

    Ferreira, Marisa; Monteiro, Silvia S.; Torres, Jordi; Oliveira, Isabel; Sequeira, Marina; López, Alfredo

    2016-01-01

    The coastal preferences of harbour porpoise (Phocoena phocoena) intensify their exposure to human activities. The harbour porpoise Iberian population is presently very small and information about the threats it endures is vital for the conservation efforts that are being implemented to avoid local extinction. The present study explored the possible relation between the accumulation of trace elements by porpoises and their sex, body length, nutritional state, presence of parasites and gross pathologies. The concentrations of arsenic (As), cadmium (Cd), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), zinc (Zn) and selenium (Se) were evaluated in 42 porpoises stranded in Portugal between 2005 and 2013. Considering European waters, porpoises stranded in Portugal present the highest Hg concentrations and the lowest Cd concentrations, which may reflect dietary preferences and the geographic availability of these pollutants. While no effect of sex on trace element concentrations was detected, there was a positive relationship between porpoise body length and the concentration of Cd, Hg and Pb. Animals in worse nutritional condition showed higher levels of Zn. Harbour porpoises with high parasite burdens showed lower levels of Zn and As in all analysed tissues and also lower levels of renal Ni, while those showing gross pathologies presented higher Zn and Hg levels. This is the first data on the relationship between trace elements and health-related variables in porpoises from southern European Atlantic waters, providing valuable baseline information about the contamination status of this vulnerable population. - Highlights: • High levels of mercury in harbour porpoises from Portugal. • Evidence of bioaccumulation of non-essential trace elements. • Presence of parasites influenced some essential trace elements. • Evidence of nutritional state effect on Zn levels. • Presence of gross pathologies influenced Zn and Hg levels. - The small harbour

  5. Stabilisation goals for concentrations of climate-relevant gaseous emissions: Effects and emission pathways. Final report; Stabilisierungsziele fuer Treibhausgaskonzentrationen: Eine Abschaetzung der Auswirkungen und der Emissionspfade. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Onigkeit, J.; Alcamo, J.; Kaspar, F.; Roesch, T.

    2000-04-01

    Two different stabilisation goals were assumed, i.e. 550 ppm and 450 ppm of carbon dioxide. First, the global anthropogenic carbon dioxide emissions were calculated that are permissible to reach these goals. Secondly, the global and regional environmental effects of these concentration goals were assessed. In this, carbon dioxide, nitric oxides and methane emissions from power generation, industry and agriculture were considered. Apart from an investigation of the global reduction strategies required, a key was developed for sharing the global reduction loads between Annex B countries and non-Annex B countries. To reach a stable concentration of 550 ppm carbon dioxide in the atmosphere, the global anthropogenic carbon dioxide emissions per annum may increase slightly until 2030 but must be lowered to the 1990 level by 2100. In the case of 450 ppm, the 1990 level must even be halved by 2100. The consequences of climate change for agriculture, natural vegetation, availability of water, and sea levels were investigated in consideration of regional variations in carbon dioxide emissions and emission reduction measures. In spite of extensive emission control, the area of reduced agricultural productivity will grow rapidly in both cases, and natural vegetation will be endangered, although with strong regional variations. [German] Ausgehend von zwei langfristigen Klimaschutzzielen (Stabilisierung der atmosphaerischen CO{sub 2}-Konzentration bei 550 ppm und bei 450 ppm) wurde mit Hilfe des IMAGE 2.1 Modells: (1) Eine Berechnung der globalen anthropogenen Treibhausgasemissionen durchgefuehrt, die zwischen 1990 und 2100 erlaubt sind, um diese Konzentrationsziele zu erreichen. (2) Wurde eine Abschaetzung der globalen und regionalen Umweltauswirkungen durch den Klimawandel durchgefuehrt, der mit diesen Konzentrationszielen einhergeht. Bei der Analyse wurden CO{sub 2}-, N{sub 2}O- und CH{sub 4} Emissionen aus dem Energie/Industrie- und dem landwirtschaftlichen Sektor

  6. Biological control of short-term variations in the concentration of DMSP and DMS during a Phaeocystis spring bloom

    NARCIS (Netherlands)

    van Duyl, FC; Gieskes, WWC; Kop, AJ; Lewis, WE

    1998-01-01

    In the spring of 1995. short-term variations in the concentration of particulate and dissolved dimethylsulfoniopropionate (DMSP) and dimethylsulfide (DMS) were monitored in the western Wadden Sea, a shallow coastal region in open connection with the North Sea. Significant correlations were found

  7. The Compact and Biologically Relevant Structure of Inter-α-inhibitor Is Maintained by the Chondroitin Sulfate Chain and Divalent Cations.

    Science.gov (United States)

    Scavenius, Carsten; Nikolajsen, Camilla Lund; Stenvang, Marcel; Thøgersen, Ida B; Wyrożemski, Łukasz; Wisniewski, Hans-Georg; Otzen, Daniel E; Sanggaard, Kristian W; Enghild, Jan J

    2016-02-26

    Inter-α-inhibitor is a proteoglycan of unique structure. The protein consists of three subunits, heavy chain 1, heavy chain 2, and bikunin covalently joined by a chondroitin sulfate chain originating at Ser-10 of bikunin. Inter-α-inhibitor interacts with an inflammation-associated protein, tumor necrosis factor-inducible gene 6 protein, in the extracellular matrix. This interaction leads to transfer of the heavy chains from the chondroitin sulfate of inter-α-inhibitor to hyaluronan and consequently to matrix stabilization. Divalent cations and heavy chain 2 are essential co-factors in this transfer reaction. In the present study, we have investigated how divalent cations in concert with the chondroitin sulfate chain influence the structure and stability of inter-α-inhibitor. The results showed that Mg(2+) or Mn(2+), but not Ca(2+), induced a conformational change in inter-α-inhibitor as evidenced by a decrease in the Stokes radius and a bikunin chondroitin sulfate-dependent increase of the thermodynamic stability. This structure was shown to be essential for the ability of inter-α-inhibitor to participate in extracellular matrix stabilization. In addition, the data revealed that bikunin was positioned adjacent to both heavy chains and that the two heavy chains also were in close proximity. The chondroitin sulfate chain interacted with all protein components and inter-α-inhibitor dissociated when it was degraded. Conventional purification protocols result in the removal of the Mg(2+) found in plasma and because divalent cations influence the conformation and affect function it is important to consider this when characterizing the biological activity of inter-α-inhibitor. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. Employment of modified Fe3 O4 nanoparticles using thermo-sensitive polymer for extraction and pre-concentration of cefexime in biological samples.

    Science.gov (United States)

    Naghibi, Saman; Sahebi, Hamed

    2018-02-01

    Cefexime is a useful antibiotic that can be prescribed to treat bacterial infections. Nanoparticles have been widely marketed as a universal solution among scientists. Many studies have been performed to modify nanoparticles to make them functional as extraction and pre-concentration agents and drug carriers. Temperature-sensitive polymers belong to a group of substances that undergo a major change in their physical features in response to temperature. Recently developed polymers can be used in many different areas, including modification of nanoparticles. In order to modify this nanoparticle, grafting copolymerization of Fe 3 O 4 nanoparticles was performed using poly (N-vinylcaprolactam) and 3-allyloxy-1,2-propanediol. The optimum conditions for pre-concentration of cefexime were studied. Under these optimum conditions, extraction recovery of biological samples in the range of 71-89% was obtained. The limit of detection and precision of proposed method were 4.5 × 10 -4  μg mL -1 and analysis of cefexime, in biological samples using the proposed method, the ability of this method to extract and pre-concentrate cefexime was confirmed. Also, satisfactory results from an in vitro study on drug release in simulated intestine media were obtained. Copyright © 2017 John Wiley & Sons, Ltd.

  9. Compilation of selected marine radioecological data for the US Subseabed Program: Summaries of available radioecological concentration factors and biological half-lives

    International Nuclear Information System (INIS)

    Gomez, L.S.; Marietta, M.G.; Jackson, D.W.

    1987-04-01

    The US Subseabed Disposal Program has compiled an extensive concentration factor and biological half-life data base from the international marine radioecological literature. A microcomputer-based data management system has been implemented to provide statistical and graphic summaries of these data. The data base is constructed in a manner which allows subsets to be sorted using a number of interstudy variables such as organism category, tissue/organ category, geographic location (for in situ studies), and several laboratory-related conditions (e.g., exposure time and exposure concentration). This report updates earlier reviews and provides summaries of the tabulated data. In addition to the concentration factor/biological half-life data base, we provide an outline of other published marine radioecological works. Our goal is to present these data in a form that enables those concerned with predictive assessment of radiation dose in the marine environment to make a more judicious selection of data for a given application. 555 refs., 19 figs., 7 tabs

  10. Compilation of selected marine radioecological data for the US Subseabed Program: Summaries of available radioecological concentration factors and biological half-lives

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, L.S.; Marietta, M.G.; Jackson, D.W.

    1987-04-01

    The US Subseabed Disposal Program has compiled an extensive concentration factor and biological half-life data base from the international marine radioecological literature. A microcomputer-based data management system has been implemented to provide statistical and graphic summaries of these data. The data base is constructed in a manner which allows subsets to be sorted using a number of interstudy variables such as organism category, tissue/organ category, geographic location (for in situ studies), and several laboratory-related conditions (e.g., exposure time and exposure concentration). This report updates earlier reviews and provides summaries of the tabulated data. In addition to the concentration factor/biological half-life data base, we provide an outline of other published marine radioecological works. Our goal is to present these data in a form that enables those concerned with predictive assessment of radiation dose in the marine environment to make a more judicious selection of data for a given application. 555 refs., 19 figs., 7 tabs.

  11. A non-invasive diffuse reflectance calibration-free method for absolute determination of exogenous biochemicals concentration in biological tissues

    Science.gov (United States)

    Lappa, Alexander V.; Kulikovskiy, Artem N.; Busarov, Oleg G.

    2014-03-01

    The paper presents a new method for distant non-destructive determination of concentration of light absorbing admixtures in turbid media. In particular, it is intended for non-invasive in vivo control of accumulation in patient tissues of various biochemicals introduced to the patients for chemotherapy, photodynamic therapy or diagnostics. It is require that the admixture absorption spectrum should have a clearly marked peak in the wavelength region where the pure medium one varies regularly. Fluorescence of admixtures is not required. The method uses the local diffuse reflectance spectroscopy with optical fiber probe including one emitting and two reading There are several features in the method: the value to be determined is absolute concentration of admixtures; the method needs no calibration measurements on phantoms; it needs no reference measurements on sample with zero admixture concentration; it uses a two parametric kinetic light propagation model and original algorithms to resolve direct and inverse tasks of radiation transport theory. Experimental testing passed with tissue equivalent phantoms and different admixtures, including a chlorine photosensitizer, showed accuracy under 10% in all cases.

  12. Measurement of Androgen and Estrogen Concentrations in Cord Blood: Accuracy, Biological Interpretation and Applications to Understanding Human Behavioural Development

    Directory of Open Access Journals (Sweden)

    Lauren P Hollier

    2014-05-01

    Full Text Available Accurately measuring hormone exposure during prenatal life presents a methodological challenge and there is currently no ‘gold standard’ approach. Ideally, circulating fetal hormone levels would be measured at repeated time points during pregnancy. However, it is not currently possible to obtain fetal blood samples without significant risk to the fetus, and therefore surrogate markers of fetal hormone levels must be utilized. Umbilical cord blood can be readily obtained at birth and largely reflects fetal circulation in late gestation. This review examines the accuracy and biological interpretation of the measurement of androgens and estrogens in cord blood. The use of cord blood hormones to understand and investigate human development is then discussed.

  13. Trace metal concentrations in Posidonia oceanica of North Corsica (northwestern Mediterranean Sea: use as a biological monitor?

    Directory of Open Access Journals (Sweden)

    Gosselin Marc

    2006-09-01

    Full Text Available Abstract Background Within semi-closed areas like the Mediterranean Sea, anthropic wastes tend to concentrate in the environment. Metals, in particular, are known to persist in the environment and can affect human health due to accumulation in the food chain. The seagrass Posidonia oceanica, widely found in Mediterranean coastal waters, has been chosen as a "sentinel" to quantify the distribution of such pollutants within the marine environment. Using a technique similar to dendrochronology in trees, it can act as an indicator of pollutant levels over a timeframe of several months to years. In the present study, we measured and compared the levels of eight trace metals (Cr, Ni, Cu, Zn, As, Se, Cd, and Pb in sheaths dated by lepidochronology and in leaves of shoots sampled from P. oceanica meadows collected from six offshore sites in northern Corsica between 1988 and 2004; in the aim to determine 1 the spatial and 2 temporal variations of these metals in these areas and 3 to compared these two types of tissues. Results We found low trace metal concentrations with no increase over the last decade, confirming the potential use of Corsican seagrass beds as reference sites for the Mediterranean Sea. Temporal trends of trace metal concentrations in sheaths were not significant for Cr, Ni, Cu, As or Se, but Zn, Cd, and Pb levels decreased, probably due to the reduced anthropic use of these metals. Similar temporal trends between Cu levels in leaves (living tissue and in sheaths (dead tissue demonstrated that lepidochronology linked with Cu monitoring is effective for surveying the temporal variability of this metal. Conclusion Leaves of P. oceanica can give an indication of the metal concentration in the environment over a short time period (months with good accuracy. On the contrary, sheaths, which gave an indication of changes over long time periods (decades, seem to be less sensitive to variations in the metal concentration in the environment

  14. In vivo degradation behavior and biological activity of some new Mg-Ca alloys with concentration's gradient of Si for bone grafts

    Science.gov (United States)

    Trincă, Lucia Carmen; Fântânariu, Mircea; Solcan, Carmen; Trofin, Alina Elena; Burtan, Liviu; Acatrinei, Dumitru Mihai; Stanciu, Sergiu; Istrate, Bogdan; Munteanu, Corneliu

    2015-10-01

    Magnesium based alloys, especially Mg-Ca alloys, are biocompatible substrates with mechanical properties similar to those of bones. The biodegradable alloys of Mg-Ca provide sufficient mechanical strength in load carrying applications as opposed to biopolymers and also they avoid stress shielding and secondary surgery inherent with permanent metallic implant materials. The main issue facing a biodegradable Mg-Ca alloy is the fast degradation in the aggressive physiological environment of the body. The alloy's corrosion is proportional with the dissolution of the Mg in the body: the reaction with the water generates magnesium hydroxide and hydrogen. The accelerated corrosion will lead to early loss of the alloy's mechanical integrity. The degradation rate of an alloy can be improved mainly through tailoring the composition and by carrying out surface treatments. This research focuses on the ability to adjust degradation rate of Mg-Ca alloys by an original method and studies the biological activity of the resulted specimens. A new Mg-Ca alloy, with a Si gradient concentration from the surface to the interior of the material, was obtained. The surface morphology was investigated using scanning electron microscopy (VegaTescan LMH II, SE detector, 30 kV), X-ray diffraction (X'Pert equipment) and energy dispersive X-ray (Bruker EDS equipment). In vivo degradation behavior, biological compatibility and activity of Mg-Ca alloys with/without Si gradient concentration were studied with an implant model (subcutaneous and bony) in rats. The organism response to implants was characterized by using radiological (plain X-rays and computed tomography), biochemical and histological methods of investigation. The results sustained that Si gradient concentration can be used to control the rate of degradation of the Mg-Ca alloys for enhancing their biologic activity in order to facilitate bone tissue repair.

  15. Solar ultraviolet radiation induces biological alterations in human skin in vitro: Relevance of a well-balanced UVA/UVB protection

    Directory of Open Access Journals (Sweden)

    Françoise Bernerd

    2012-01-01

    Full Text Available Cutaneous damages such as sunburn, pigmentation, and photoaging are known to be induced by acute as well as repetitive sun exposure. Not only for basic research, but also for the design of the most efficient photoprotection, it is crucial to understand and identify the early biological events occurring after ultraviolet (UV exposure. Reconstructed human skin models provide excellent and reliable in vitro tools to study the UV-induced alterations of the different skin cell types, keratinocytes, fibroblasts, and melanocytes in a dose- and time-dependent manner. Using different in vitro human skin models, the effects of UV light (UVB and UVA were investigated. UVB-induced damages are essentially epidermal, with the typical sunburn cells and DNA lesions, whereas UVA radiation-induced damages are mostly located within the dermal compartment. Pigmentation can also be obtained after solar simulated radiation exposure of pigmented reconstructed skin model. Those models are also highly adequate to assess the potential of sunscreens to protect the skin from UV-associated damage, sunburn reaction, photoaging, and pigmentation. The results showed that an effective photoprotection is provided by broad-spectrum sunscreens with a potent absorption in both UVB and UVA ranges.

  16. Solar ultraviolet radiation induces biological alterations in human skin in vitro: relevance of a well-balanced UVA/UVB protection.

    Science.gov (United States)

    Bernerd, Francoise; Marionnet, Claire; Duval, Christine

    2012-06-01

    Cutaneous damages such as sunburn, pigmentation, and photoaging are known to be induced by acute as well as repetitive sun exposure. Not only for basic research, but also for the design of the most efficient photoprotection, it is crucial to understand and identify the early biological events occurring after ultraviolet (UV) exposure. Reconstructed human skin models provide excellent and reliable in vitro tools to study the UV-induced alterations of the different skin cell types, keratinocytes, fibroblasts, and melanocytes in a dose- and time-dependent manner. Using different in vitro human skin models, the effects of UV light (UVB and UVA) were investigated. UVB-induced damages are essentially epidermal, with the typical sunburn cells and DNA lesions, whereas UVA radiation-induced damages are mostly located within the dermal compartment. Pigmentation can also be obtained after solar simulated radiation exposure of pigmented reconstructed skin model. Those models are also highly adequate to assess the potential of sunscreens to protect the skin from UV-associated damage, sunburn reaction, photoaging, and pigmentation. The results showed that an effective photoprotection is provided by broad-spectrum sunscreens with a potent absorption in both UVB and UVA ranges.

  17. The synthesis of hydroxyapatite with different crystallinities by controlling the concentration of recombinant CEMP1 for biological application

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaofeng [Hospital of Stomatology, Medical School of Nanjing University, Nanjing, Jiangsu 210093 (China); Liu, Yu, E-mail: lyvette@163.com [Hospital of Stomatology, Medical School of Nanjing University, Nanjing, Jiangsu 210093 (China); Yang, Jie; Wu, Wenlei; Miao, Leiying; Yu, Yijun [Hospital of Stomatology, Medical School of Nanjing University, Nanjing, Jiangsu 210093 (China); Yang, Xuebin [Biomaterials and Tissue Engineering Group, Leeds Dental Institute, University of Leeds (United Kingdom); Sun, Weibin, E-mail: wbsun@nju.edu.cn [Hospital of Stomatology, Medical School of Nanjing University, Nanjing, Jiangsu 210093 (China)

    2016-02-01

    Cementum protein 1 (CEMP1) has been reported to be cementum specific and it plays a role in the properties and structure of cementum mineralization. This study was carried out to test the hypothesis that, CEMP1 had the capacity to guide ordered HA formation as it accumulated at targeting site. Crystals induced by protein were prepared by biomimetic method. The effects of CEMP1 concentrations (0–100 μg/ml) on the rate of calcium phosphate precipitation was monitored during 48 h, while the formed mineral phases were assessed utilizing transmission electron microscope (TEM), selected area electron diffraction (SAED), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results showed that recombinant cementum protein 1 (rhCEMP1) affected the crystal nucleation and growth. At lower rhCEMP1 concentrations (0–50 μg/ml), limited mineral formation occurred and only small bundles of HA crystals were found. However, with 100 μg/ml of rhCEMP1, a predominance of organized linear needle-like HA crystals was observed. FTIR revealed the characteristic bands of HA appearing at 1106 cm{sup −1}, 557 cm{sup −1}, and 598 cm{sup −1}. Therefore, increasing the concentration of rhCEMP1 can lead to the formation of ordered bundles of HA crystals in vitro. - Highlights: • We produce recombinant human cementum protein 1 (rhCEMP1). • We synthesize hydroxyapatite/rhCEMP1 with different crystallinities. • Increase of rhCEMP1 leads to the formation of ordered bundles of HA crystals.

  18. Mercury concentrations in Alaska Pacific halibut muscle relative to stable isotopes of C and N and other biological variables

    International Nuclear Information System (INIS)

    Bentzen, Rebecca; Castellini, J. Margaret; Gerlach, Robert; Dykstra, Claude; O'Hara, Todd

    2016-01-01

    Total mercury concentrations ([THg]), δ 15 N and δ 13 C values were determined in muscle of 693 Pacific halibut caught in International Pacific Halibut Commission setline surveys in Alaska (2002 − 2011). Project goals were to evaluate whether 1) δ 15 N and δ 13 C varied with region, age, sex and length of halibut, and 2) muscle [THg] varied with δ 15 N and δ 13 C (feeding ecology) while accounting for sex, length, and region. Variation in [THg] was explained, in part, by halibut feeding ecology as [THg] increased with trophic position (increasing δ 15 N). Halibut from the western Aleutian Island region were the exception, with overall lower δ 15 N values and significantly higher [THg] than halibut from other Alaskan waters. This [THg] pattern has been observed in other Aleutian biota, possibly the result of northeasterly atmospheric movement of mercury emissions from Asia and/or other local sources and processes. The significantly lower δ 15 N values for these halibut warrants further investigation of halibut prey. - Highlights: • Mercury, δ 15 N, and δ 13 C were determined in muscle of 693 Pacific halibut in Alaska. • Variation in muscle mercury level was explained, in part, by halibut feeding ecology. • Muscle mercury concentration generally increased with relative trophic position (δ 15 N). • Western Aleutian halibut had lower δ 15 N and higher mercury than other regions. • Assessment of mercury and trophic relationships accounted for sex, size, and region.

  19. In vivo degradation behavior and biological activity of some new Mg–Ca alloys with concentration's gradient of Si for bone grafts

    Energy Technology Data Exchange (ETDEWEB)

    Trincă, Lucia Carmen, E-mail: lctrinca@uaiasi.ro [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Horticulture, Str. Aleea M. Sadoveanu, No. 3, 700490 Iasi (Romania); Fântânariu, Mircea, E-mail: mfantanariu@uaiasi.ro [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Str. Aleea M. Sadoveanu, No. 8, 700489 Iasi (Romania); Solcan, Carmen, E-mail: csolcan@yahoo.com [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Str. Aleea M. Sadoveanu, No. 8, 700489 Iasi (Romania); Trofin, Alina Elena, E-mail: aetrofin@yahoo.com [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Horticulture, Str. Aleea M. Sadoveanu, No. 3, 700490 Iasi (Romania); Burtan, Liviu, E-mail: lburtan@uaiasi.ro [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Str. Aleea M. Sadoveanu, No. 8, 700489 Iasi (Romania); Acatrinei, Dumitru Mihai, E-mail: dacatrinei@yahoo.com [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Str. Aleea M. Sadoveanu, No. 8, 700489 Iasi (Romania); Stanciu, Sergiu, E-mail: sergiustanciu2003@yahoo.com [“Gheorghe Asachi” Technical University, Faculty of Materials Science and Engineering, Str. Prof. D. Mangeron, No. 67, 700050 Iasi (Romania); and others

    2015-10-15

    Highlights: • A Mg–Ca alloy with Si concentration gradient was obtained as bone graft material. • Degradation rate of the Mg–Ca–Si alloy was investigated by SEM and EDAX techniques. • Subcutaneous and tibiae implants in rats were monitored by Biochemical, histological, RX and CT investigations monitored implant's evolution. • Si concentration gradient decreased the alloy degradation rate during bone healing. - Abstract: Magnesium based alloys, especially Mg–Ca alloys, are biocompatible substrates with mechanical properties similar to those of bones. The biodegradable alloys of Mg–Ca provide sufficient mechanical strength in load carrying applications as opposed to biopolymers and also they avoid stress shielding and secondary surgery inherent with permanent metallic implant materials. The main issue facing a biodegradable Mg–Ca alloy is the fast degradation in the aggressive physiological environment of the body. The alloy's corrosion is proportional with the dissolution of the Mg in the body: the reaction with the water generates magnesium hydroxide and hydrogen. The accelerated corrosion will lead to early loss of the alloy's mechanical integrity. The degradation rate of an alloy can be improved mainly through tailoring the composition and by carrying out surface treatments. This research focuses on the ability to adjust degradation rate of Mg–Ca alloys by an original method and studies the biological activity of the resulted specimens. A new Mg–Ca alloy, with a Si gradient concentration from the surface to the interior of the material, was obtained. The surface morphology was investigated using scanning electron microscopy (VegaTescan LMH II, SE detector, 30 kV), X-ray diffraction (X’Pert equipment) and energy dispersive X-ray (Bruker EDS equipment). In vivo degradation behavior, biological compatibility and activity of Mg–Ca alloys with/without Si gradient concentration were studied with an implant model (subcutaneous

  20. MAK and BAT values list 2014. Maximum permissible concentrations at the place of work and biological tolerance values for working materials; MAK- und BAT-Werte-Liste 2014. Maximale Arbeitsplatzkonzentrationen und Biologische Arbeitsstofftoleranzwerte

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-11-01

    The book on the MAK (maximum permissible concentrations at the place of work) and BAT (biological tolerance values for working materials) value list 2014 includes the following chapters: (a) Maximum permissible concentrations at the place of work: definition, application and determination of MAT values, list of materials; carcinogenic working materials, sensibilizing working materials, aerosols, limiting the exposition peaks, skin resorption, MAK values during pregnancy, germ cell mutagens, specific working materials; (b) Biological tolerance values for working materials: definition and application of BAT values, list of materials, carcinogenic working materials, biological guide values, biological working material reference values.

  1. MAK and BAT values list 2013. Maximum permissible concentrations at the place of work and biological tolerance values for working materials; MAK- und BAT-Werte-Liste 2013. Maximale Arbeitsplatzkonzentrationen und Biologische Arbeitsstofftoleranzwerte

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-01

    The book on the MAK (maximum permissible concentrations at the place of work) and BAT (biological tolerance values for working materials) value list 2013 includes the following chapters: (a) Maximum permissible concentrations at the place of work: definition, application and determination of MAT values, list of materials; carcinogenic working materials, sensibilizing working materials, aerosols, limiting the exposition peaks, skin resorption, MAK values during pregnancy, germ cell mutagens, specific working materials; (b) Biological tolerance values for working materials: definition and application of BAT values, list of materials, carcinogenic working materials, biological guide values, biological working material reference values.

  2. MAK and BAT values list 2015. Maximum permissible concentrations at the place of work and biological tolerance values for working materials; MAK- und BAT-Werte-Liste 2015. Maximale Arbeitsplatzkonzentrationen und Biologische Arbeitsstofftoleranzwerte

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-11-01

    The book on the MAK (maximum permissible concentrations at the place of work) and BAT (biological tolerance values for working materials) value list 2015 includes the following chapters: (a) Maximum permissible concentrations at the place of work: definition, application and determination of MAT values, list of materials; carcinogenic working materials, sensibilizing working materials, aerosols, limiting the exposition peaks, skin resorption, MAK values during pregnancy, germ cell mutagens, specific working materials; (b) Biological tolerance values for working materials: definition and application of BAT values, list of materials, carcinogenic working materials, biological guide values, biological working material reference values.

  3. Computational biology

    DEFF Research Database (Denmark)

    Hartmann, Lars Røeboe; Jones, Neil; Simonsen, Jakob Grue

    2011-01-01

    Computation via biological devices has been the subject of close scrutiny since von Neumann’s early work some 60 years ago. In spite of the many relevant works in this field, the notion of programming biological devices seems to be, at best, ill-defined. While many devices are claimed or proved t...

  4. Synthesis and biological studies of highly concentrated lisinopril-capped gold nanoparticles for CT tracking of angiotensin converting enzyme (ACE)

    Science.gov (United States)

    Ghann, William E.; Aras, Omer; Fleiter, Thorsten; Daniel, Marie-Christine

    2011-05-01

    For patients with a history of heart attack or stroke, the prevention of another cardiovascular or cerebrovascular event is crucial. The development of cardiac and pulmonary fibrosis has been associated with overexpression of tissue angiotensin-converting enzyme (ACE). Recently, gold nanoparticles (GNPs) have shown great potential as X-ray computed tomography (CT) contrast agents. Since lisinopril is an ACE inhibitor, it has been used as coating on GNPs for targeted imaging of tissue ACE in prevention of fibrosis. Herein, lisinopril-capped gold nanoparticles (LIS-GNPs) were synthesized up to a concentration of 55 mgAu/mL. Their contrast was measured using CT and the results were compared to Omnipaque, a commonly used iodine-based contrast agent. The targeting ability of these LIS-GNPs was also assessed.

  5. Relationship of Serum Vitamin D Concentrations and Allostatic Load as a Measure of Cumulative Biological Risk among the US Population: A Cross-Sectional Study.

    Directory of Open Access Journals (Sweden)

    Regina Frei

    Full Text Available The allostatic load (AL index is a multi-systemic measure of physiologic dysregulation known to be associated with chronic exposure to stress and adverse health outcomes. We examined the relationship between AL and serum 25-hydroxyvitamin D (25(OHD concentration in non-institutionalized US adults.Data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-94 were used to calculate two versions of AL including 9 biomarkers and another two with 14 biomarkers (systolic and diastolic blood pressure, pulse rate, serum cholesterol, serum HDL-cholesterol, glycated hemoglobin, sex-specific waist-to-hip ratio, serum albumin, and serum C-reactive protein for AL1, and, additionally body mass index, serum triglyceride, serum creatinine, and serum herpes I & II antibodies for AL2, each set defined by predefined cut-offs or by quartiles. Serum vitamin D concentration was ranked into quartiles. Logistic regression, Poisson regression and linear regression were used to examine the association of serum 25(OHD concentrations on AL, after adjusting for biological, physiological, socioeconomic, lifestyle, and health variables.Odds Ratios (OR for high AL of the lowest 25(OHD serum quartile were between 1.45 (95% CI: 1.28, 1.67 and 1.79 (95% CI: 1.39, 2.32 for the fully adjusted model, depending on AL version. Inverse relationships between vitamin D serum concentrations were observed for all AL versions and every adjustment. This relationship was consistent after stratification by sex, age or ethnic background. Sensitivity to low 25(OHD concentrations was highest among the youngest group (20-39 years with an OR of 2.11 (95% CI: 1.63, 2.73 for the lowest vitamin D quartile Q1.Vitamin D had a consistent and statistically significant inverse association with all tested models of high AL, which remained consistent after adjusting for biological, socioeconomic, lifestyle and health variables. Our study adds evidence linking low 25(OHD

  6. Concentration levels of rare-earth elements and thorium on plants from the Morro de Ferro environment as an indicator for the biological availability of transuranium elements

    International Nuclear Information System (INIS)

    Miekeley, N.; Casartelli, E.A.; Dotto, R.M.

    1994-01-01

    Plants and soils from a natural thorium and rare-earth element occurrence (Morro do Ferro, Brazil) were analyzed by alpha spectrometry (Th) and ICP-AES (REE), after pre-concentration of the elements by solvent extraction, co-precipitation and ion exchange procedures. Leaching experiments with humic acid solutions and different soils were performed to estimate the fraction of elements biologically available. High concentrations of the light rare-earth elements (LREE) and of Th, reaching some hundreds of μg/g-ash, were measured in plant leaves from the areas of the highest concentration of these elements in soil and in near-surface waters. Chondrite normalized REE plots of plant leaves and corresponding soils are very similar, suggesting that there is no significant fractionation between the REE during uptake from the soil solution and incorporation into the leaves. However, Ce-depletion was observed for some plant species, increasing for Solanum ciliatum in the sequence: leaves -3 to 10 -2 . Leaching experiments confirmed the importance of humic acid complexation for the bio-uptake of Th and REE and further showed that only a very small fraction of these elements in soil is leachable. The implications of these results on the calculated CR's will be discussed. (author) 26 refs.; 5 figs.; 5 tabs

  7. Long-term exposure of CdTe quantum dots on PC12 cellular activity and the determination of optimum non-toxic concentrations for biological use

    Directory of Open Access Journals (Sweden)

    Gérard Valérie A

    2010-03-01

    Full Text Available Abstract Background The unique and tuneable photonic properties of Quantum Dots (QDs have made them potentially useful tools for imaging biological entities. However, QDs though attractive diagnostic and therapeutic tools, have a major disadvantage due to their inherent cytotoxic nature. The cellular interaction, uptake and resultant toxic influence of CdTe QDs (gelatinised and non-gelatinised Thioglycolic acid (TGA capped have been investigated with pheochromocytoma 12 (PC12 cells. In conjunction to their analysis by confocal microscopy, the QD - cell interplay was explored as the QD concentrations were varied over extended (up to 72 hours co-incubation times. Coupled to this investigation, cell viability, DNA quantification and cell proliferation assays were also performed to compare and contrast the various factors leading to cell stress and ultimately death. Results Thioglycolic acid (TGA stabilised CdTe QDs (gel and non - gel were co-incubated with PC12 cells and investigated as to how their presence influenced cell behaviour and function. Cell morphology was analysed as the QD concentrations were varied over co-incubations up to 72 hours. The QDs were found to be excellent fluorophores, illuminating the cytoplasm of the cells and no deleterious effects were witnessed at concentrations of ~10-9 M. Three assays were utilised to probe how individual cell functions (viability, DNA quantification and proliferation were affected by the presence of the QDs at various concentrations and incubation times. Cell response was found to not only be concentration dependant but also influenced by the surface environment of the QDs. Gelatine capping on the surface acts as a barrier towards the leaking of toxic atoms, thus reducing the negative impact of the QDs. Conclusion This study has shown that under the correct conditions, QDs can be routinely used for the imaging of PC12 cells with minimal adverse effects. We have found that PC12 cells are highly

  8. Long-term exposure of CdTe quantum dots on PC12 cellular activity and the determination of optimum non-toxic concentrations for biological use

    LENUS (Irish Health Repository)

    Prasad, Babu R

    2010-03-25

    Abstract Background The unique and tuneable photonic properties of Quantum Dots (QDs) have made them potentially useful tools for imaging biological entities. However, QDs though attractive diagnostic and therapeutic tools, have a major disadvantage due to their inherent cytotoxic nature. The cellular interaction, uptake and resultant toxic influence of CdTe QDs (gelatinised and non-gelatinised Thioglycolic acid (TGA) capped) have been investigated with pheochromocytoma 12 (PC12) cells. In conjunction to their analysis by confocal microscopy, the QD - cell interplay was explored as the QD concentrations were varied over extended (up to 72 hours) co-incubation times. Coupled to this investigation, cell viability, DNA quantification and cell proliferation assays were also performed to compare and contrast the various factors leading to cell stress and ultimately death. Results Thioglycolic acid (TGA) stabilised CdTe QDs (gel and non - gel) were co-incubated with PC12 cells and investigated as to how their presence influenced cell behaviour and function. Cell morphology was analysed as the QD concentrations were varied over co-incubations up to 72 hours. The QDs were found to be excellent fluorophores, illuminating the cytoplasm of the cells and no deleterious effects were witnessed at concentrations of ~10-9 M. Three assays were utilised to probe how individual cell functions (viability, DNA quantification and proliferation) were affected by the presence of the QDs at various concentrations and incubation times. Cell response was found to not only be concentration dependant but also influenced by the surface environment of the QDs. Gelatine capping on the surface acts as a barrier towards the leaking of toxic atoms, thus reducing the negative impact of the QDs. Conclusion This study has shown that under the correct conditions, QDs can be routinely used for the imaging of PC12 cells with minimal adverse effects. We have found that PC12 cells are highly susceptible to

  9. Validation of odor concentration from mechanical-biological treatment piles using static chamber and wind tunnel with different wind speed values.

    Science.gov (United States)

    Szyłak-Szydłowski, Mirosław

    2017-09-01

    The basic principle of odor sampling from surface sources is based primarily on the amount of air obtained from a specific area of the ground, which acts as a source of malodorous compounds. Wind tunnels and flux chambers are often the only available, direct method of evaluating the odor fluxes from small area sources. There are currently no widely accepted chamber-based methods; thus, there is still a need for standardization of these methods to ensure accuracy and comparability. Previous research has established that there is a significant difference between the odor concentration values obtained using the Lindvall chamber and those obtained by a dynamic flow chamber. Thus, the present study compares sampling methods using a streaming chamber modeled on the Lindvall cover (using different wind speeds), a static chamber, and a direct sampling method without any screens. The volumes of chambers in the current work were similar, ~0.08 m 3 . This study was conducted at the mechanical-biological treatment plant in Poland. Samples were taken from a pile covered by the membrane. Measured odor concentration values were between 2 and 150 ou E /m 3 . Results of the study demonstrated that both chambers can be used interchangeably in the following conditions: odor concentration is below 60 ou E /m 3 , wind speed inside the Lindvall chamber is below 0.2 m/sec, and a flow value is below 0.011 m 3 /sec. Increasing the wind speed above the aforementioned value results in significant differences in the results obtained between those methods. In all experiments, the results of the concentration of odor in the samples using the static chamber were consistently higher than those from the samples measured in the Lindvall chamber. Lastly, the results of experiments were employed to determine a model function of the relationship between wind speed and odor concentration values. Several researchers wrote that there are no widely accepted chamber-based methods. Also, there is still a

  10. Application of dried-droplets deposited on pre-cut filter paper disks for quantitative LA-ICP-MS imaging of biologically relevant minor and trace elements in tissue samples.

    Science.gov (United States)

    Bonta, Maximilian; Hegedus, Balazs; Limbeck, Andreas

    2016-02-18

    In this work, a novel calibration approach for minor and trace element quantification in LA-ICP-MS imaging of biological tissues is presented. Droplets of aqueous standard solutions are deposited onto pre-cut pieces of filter paper, allowed to dry, and sputtered with a thin gold layer for use as pseudo-internal standard. Analysis of the standards using LA-ICP-MS is performed using radial line-scans across the filters. In contrast to conventionally used preparation of matrix-matched tissue standards, the dried-droplet approach offers a variety of advantages: The standards are easy to prepare, no characterization of the standards using acid digestion is required, no handling of biological materials is necessary, and the concentration range, as well the number of investigated analytes is almost unlimited. The proposed quantification method has been verified using homogenized tissue standards with known analyte concentrations before being applied to a human malignant mesothelioma biopsy from a patient who had not received any chemotherapeutic treatment. Elemental distribution images were acquired at a lateral resolution of 40 μm per pixel, limits of detection ranging from 0.1 μg g(-1) (Mn, Ni, Cu, Zn) to 13.2 μg g(-1) (K) were reached. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Systems Biology Reveals Cigarette Smoke-Induced Concentration-Dependent Direct and Indirect Mechanisms That Promote Monocyte-Endothelial Cell Adhesion.

    Science.gov (United States)

    Poussin, Carine; Laurent, Alexandra; Peitsch, Manuel C; Hoeng, Julia; De Leon, Hector

    2015-10-01

    Cigarette smoke (CS) affects the adhesion of monocytes to endothelial cells, a critical step in atherogenesis. Using an in vitro adhesion assay together with innovative computational systems biology approaches to analyze omics data, our study aimed at investigating CS-induced mechanisms by which monocyte-endothelial cell adhesion is promoted. Primary human coronary artery endothelial cells (HCAECs) were treated for 4 h with (1) conditioned media of human monocytic Mono Mac-6 (MM6) cells preincubated with low or high concentrations of aqueous CS extract (sbPBS) from reference cigarette 3R4F for 2 h (indirect treatment, I), (2) unconditioned media similarly prepared without MM6 cells (direct treatment, D), or (3) freshly generated sbPBS (fresh direct treatment, FD). sbPBS promoted MM6 cells-HCAECs adhesion following I and FD, but not D. In I, the effect was mediated at a low concentration through activation of vascular inflammation processes promoted in HCAECs by a paracrine effect of the soluble mediators secreted by sbPBS-treated MM6 cells. Tumor necrosis factor α (TNFα), a major inducer, was actually shed by unstable CS compound-activated TNFα-converting enzyme. In FD, the effect was triggered at a high concentration that also induced some toxicity. This effect was mediated through an yet unknown mechanism associated with a stress damage response promoted in HCAECs by unstable CS compounds present in freshly generated sbPBS, which had decayed in D unconditioned media. Aqueous CS extract directly and indirectly promotes monocytic cell-endothelial cell adhesion in vitro via distinct concentration-dependent mechanisms. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. MAK and BAT values list 2017. Maximum permissible concentrations at the place of work and biological tolerance values for working materials; MAK- und BAT-Werte-Liste 2017. Maximale Arbeitsplatzkonzentrationen und Biologische Arbeitsstofftoleranzwerte

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-08-01

    The MAK and BAT values list 2017 includes the maximum permissible concentrations at the place of work and biological tolerance values for working materials. The following working materials are covered: carcinogenic working materials, sensitizing materials and aerosols. The report discusses the restriction of exposure peaks, skin resorption, MAK (maximum working place concentration) values during pregnancy, germ cell mutagens and specific working materials. Importance and application of BAT (biological working material tolerance) values, list of materials, carcinogens, biological guide values and reference values are also included.

  13. CRISPR-Cas: biology, mechanisms and relevance

    Science.gov (United States)

    Hille, Frank

    2016-01-01

    Prokaryotes have evolved several defence mechanisms to protect themselves from viral predators. Clustered regularly interspaced short palindromic repeats (CRISPR) and their associated proteins (Cas) display a prokaryotic adaptive immune system that memorizes previous infections by integrating short sequences of invading genomes—termed spacers—into the CRISPR locus. The spacers interspaced with repeats are expressed as small guide CRISPR RNAs (crRNAs) that are employed by Cas proteins to target invaders sequence-specifically upon a reoccurring infection. The ability of the minimal CRISPR-Cas9 system to target DNA sequences using programmable RNAs has opened new avenues in genome editing in a broad range of cells and organisms with high potential in therapeutical applications. While numerous scientific studies have shed light on the biochemical processes behind CRISPR-Cas systems, several aspects of the immunity steps, however, still lack sufficient understanding. This review summarizes major discoveries in the CRISPR-Cas field, discusses the role of CRISPR-Cas in prokaryotic immunity and other physiological properties, and describes applications of the system as a DNA editing technology and antimicrobial agent. This article is part of the themed issue ‘The new bacteriology’. PMID:27672148

  14. Evaluating vertical concentration profile of carbon source released from slow-releasing carbon source tablets and in situ biological nitrate denitrification activity

    Science.gov (United States)

    Yeum, Y.; HAN, K.; Yoon, J.; Lee, J. H.; Song, K.; Kang, J. H.; Park, C. W.; Kwon, S.; Kim, Y.

    2017-12-01

    Slow-releasing carbon source tablets were manufactured during the design of a small-scale in situ biological denitrification system to reduce high-strength nitrate (> 30 mg N/L) from a point source such as livestock complexes. Two types of slow-releasing tablets, precipitating tablet (PT, apparent density of 2.0 g/mL) and floating tablet (FT), were prepared to achieve a vertically even distribution of carbon source (CS) in a well and an aquifer. Hydroxypropyl methylcellulose (HPMC) was used to control the release rate, and microcrystalline cellulose pH 101 (MCC 101) was added as a binder. The #8 sand was used as a precipitation agent for the PTs, and the floating agents for the FTs were calcium carbonate and citric acid. FTs floated within 30 min. and remained in water because of the buoyance from carbon dioxide, which formed during the acid-base reaction between citric acid and calcium carbonate. The longevities of PTs with 300 mg of HPMC and FTs with 400 mg of HPMC were 25.4 days and 37.3 days, respectively. We assessed vertical CS profile in a continuous flowing physical aquifer model (release test, RT) and its efficiency on biological nitrate denitrification (denitrification test, DT). During the RT, PTs, FTs and a tracer (as 1 mg rhodamine B/L) were initially injected into a well of physical aquifer model (PAM). Concentrations of CS and the tracer were monitored along the streamline in the PAM to evaluate vertical profile of CS. During the DT, the same experiment was performed as RT, except continuous injection of solution containing 30 mg N/L into the PAM to evaluate biological denitrification activity. As a result of RT, temporal profiles of CS were similar at 3 different depths of monitoring wells. These results suggest that simultaneous addition of PT and FT be suitable for achieving a vertically even distribution of the CS in the injection well and an aquifer. In DT, similar profile of CS was detected in the injection well, and nitrate was biologically

  15. Effect of tomato post-harvest fungicide treatment and storage conditions on the quality of fruits, and biological value of tomato pulp and concentrated pulp

    Directory of Open Access Journals (Sweden)

    H. Parynow

    2013-12-01

    Full Text Available The influence of storage conditions on the quality of tomato fruits was tested. The rate of ripening was established in normal air, where tomatoes ripen quickly, under controlled atmosphere where they ripen more slowly and under low pressure, where they ripen slowest. The influence of post-harvest benomyl or methylthiophanate treatment on tomato rot, ripening, and biological value were examined. Post-harvest tomato treatment did not reduce fruit rot. The color of fruits and the processed products depended on the fungicide treatment. Concentrated tomato pulp made of fruits treated with methylthiophanate was redder than the others. The fungicide treatment increased or decreased the level of some chemical substances in the fruits in dependence on the applied fungicide, storage conditions and the length of storage, e.g. tomatoes treated with benomyl and stored for 14 days contained the highest level of vitamin C under 0% CO2:3%O2 and tomatoes treated with methylthiophanate contained the highest level of vitamin C under 38 mm Hg. Degradation of vitamin C in pulp was faster than in the concentrated pulp. Tomato pulp made of tomatoes treated with methylthiophanate contained the lowest level of vitamin C.

  16. In vitro killing of Escherichia coli, Staphylococcus pseudintermedius and Pseudomonas aeruginosa by enrofloxacin in combination with its active metabolite ciprofloxacin using clinically relevant drug concentrations in the dog and cat.

    Science.gov (United States)

    Blondeau, J M; Borsos, S; Blondeau, L D; Blondeau, B J

    2012-03-23

    Enrofloxacin is a fluoroquinolone antibacterial agent used to treat infections in companion animals. Enrofloxacin's antimicrobial spectrum includes Gram positive and Gram-negative bacteria and demonstrates concentration-dependent bacteriocidal activity. In dogs and cats, enrofloxacin is partially metabolized to ciprofloxacin and both active agents circulate simultaneously in treated animals at ratios of approximately 60-70% enrofloxacin to 30-40% ciprofloxacin. We were interested in determining the killing of companion animal isolates of Escherichia coli, Staphylococcus pseudintermedius and Pseudomonas aeruginosa by enrofloxacin and ciprofloxacin combined using clinically relevant drug concentrations and ratios. For E. coli isolates exposed to 2.1 and 4.1μg/ml of enrofloxacin/ciprofloxacin at 50:50, 60:40 and 70:30 ratios, a 1.7-2.5log(10) reduction (94-99% kill) was seen following 20min of drug exposure; 0.89-1.7log(10) (92-99% kill) of S. pseudintermedius following 180min of drug exposure; 0.85-3.4log(10) (98-99% kill) of P. aeruginosa following 15min of drug exposure. Killing of S. pseudintermedius was enhanced in the presence of enrofloxacin whereas killing of P. aeruginosa was enhanced in the presence of ciprofloxacin. Antagonism was not seen when enrofloxacin and ciprofloxacin were used in kill assays. The unique feature of partial metabolism of enrofloxacin to ciprofloxacin expands the spectrum of enhanced killing of common companion animal pathogens. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Effects of concentration of Ag nanoparticles on surface structure and in vitro biological responses of oxide layer on pure titanium via plasma electrolytic oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ki Ryong; Kim, Yeon Sung; Kim, Gye Won [Department of Materials Science and Engineering, Hanyang University, Ansan 425-791 (Korea, Republic of); Yang, Hae Woong [School of Materials Science and Engineering, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Ko, Young Gun, E-mail: younggun@ynu.ac.kr [School of Materials Science and Engineering, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Shin, Dong Hyuk, E-mail: dhshin@hanyang.ac.kr [Department of Materials Science and Engineering, Hanyang University, Ansan 425-791 (Korea, Republic of)

    2015-08-30

    Highlights: • Ag nanoparticles were embedded into the oxide surface without any compositional changes. • Oxide layer from the electrolyte with 0.1 g/l Ag nanoparticles could disinfect all bacteria. • With increasing Ag nanoparticles, bone-forming ability and cell proliferation rate decrease. - Abstract: This study was to investigate how Ag nanoparticles with various concentrations affect the surface structure and in vitro biological properties of oxide layers on the pure titanium produced by a plasma electrolytic oxidation (PEO) process. For this aim, PEO processes were carried out at an AC current density of 100 mA/cm{sup 2} for 300 s in potassium pyrophosphate (K{sub 4}P{sub 2}O{sub 7}) electrolytes containing 0, 0.1, 0.3 and 0.5 g/l Ag nanoparticles. Structural investigations using scanning electron microscopy evidenced that the oxide layers showed the successful incorporation of Ag nanoparticles, and the topographical deformation of the porous surface was found when the concentration of Ag nanoparticles was more than 0.1 g/l. Based on the anti-bacterial activity of all oxide layers, the Ag nanoparticles uniformly spread were of considerable importance in triggering the disinfection of E. coli bacteria. The bone forming abilities and cell (MC3T3-E1) proliferation rates of oxide layers produced in electrolytes containing 0 and 0.1 g/l Ag nanoparticles were higher than those containing 0.3 and 0.5 g/l Ag nanoparticles. Consequently, the oxide layer on pure titanium via PEO process in the electrolyte with 0.1 g/l Ag nanoparticles exhibited better the bioactivity accompanying the anti-bacterial activity.

  18. Red wine consumption may affect sperm biology: the effects of different concentrations of the phytoestrogen myricetin on human male gamete function.

    Science.gov (United States)

    Aquila, Saveria; Santoro, Marta; De Amicis, Francesca; Guido, Carmela; Bonofiglio, Daniela; Lanzino, Marilena; Cesario, Maria Grazia; Perrotta, Ida; Sisci, Diego; Morelli, Catia

    2013-02-01

    Myricetin is a natural flavonoid, particularly enriched in red wines, whose occurrence is widespread among plants. Despite extensive research, the beneficial effects of Myricetin on human health are still controversial. Here, we tested the estrogen-like effect of the phytoestrogen Myricetin on human ejaculated sperm biology. To this aim, human normozoospermic samples were exposed to increasing concentrations (10 nM, 100 nM, and 1 µM) of Myricetin. Motility, viability, capacitation-associated biochemical changes (i.e., cholesterol efflux and tyrosine phosphorylation), acrosin activity, as well as glucose utilization and fatty-acid oxidation (i.e., glucose and lipid metabolism) were all significantly increased by low doses of Myricetin. Importantly, both estrogen receptors α and β (ERs) and phosphatidylinositol-3-OH kinase (PI3K)/AKT signaling are activated in the presence of Myricetin since these were both abrogated by specific inhibitors of each pathway. Our results show how Myricetin, through ERs and PI3K/AKT signalings, potentiates sperm function. This effect is dose-dependent at low concentrations of Myricetin (up to 100 nM), whereas higher amounts do not seem to improve any further sperm motility, viability, or other tested features, and, in some cases, they reduced or even abrogated the efficacy exerted by lower doses. Further studies are needed to elucidate if high levels of Myricetin, which could be attained even with moderate wine consumption, could synergize with endogenous estrogens in the female reproductive tract, interfering with the physiological sperm fertilization process. Copyright © 2012 Wiley Periodicals, Inc.

  19. Genetic characterization of interleukins (IL-1α, IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12A, IL-12B, IL-15 and IL-18) with relevant biological roles in lagomorphs

    Science.gov (United States)

    Neves, Fabiana; Abrantes, Joana; Almeida, Tereza; de Matos, Ana Lemos; Costa, Paulo P

    2015-01-01

    ILs, as essential innate immune modulators, are involved in an array of biological processes. In the European rabbit (Oryctolagus cuniculus) IL-1α, IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12A, IL-12B, IL-15 and IL-18 have been implicated in inflammatory processes and in the immune response against rabbit hemorrhagic disease virus and myxoma virus infections. In this study we characterized these ILs in six Lagomorpha species (European rabbit, pygmy rabbit, two cottontail rabbit species, European brown hare and American pika). Overall, these ILs are conserved between lagomorphs, including in their exon/intron structure. Most differences were observed between leporids and American pika. Indeed, when comparing both, some relevant differences were observed in American pika, such as the location of the stop codon in IL-1α and IL-2, the existence of a different transcript in IL8 and the number of cysteine residues in IL-1β. Changes at N-glycosylation motifs were also detected in IL-1, IL-10, IL-12B and IL-15. IL-1α is the protein that presents the highest evolutionary distances, which is in contrast to IL-12A where the distances between lagomorphs are the lowest. For all these ILs, sequences of human and European rabbit are more closely related than between human and mouse or European rabbit and mouse. PMID:26395994

  20. TU-H-CAMPUS-TeP3-04: Probing the Dose Enhancement Due to a Clinically-Relevant Concentration of Gold Nanoparticles and Yb-169 Gamma Rays Using PRESAGE Dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Cho, J [UT MD Anderson Cancer Center, Houston, TX (United States); Oklahoma State University, Stillwater, OK (United States); Alqathami, M; Cho, S [UT MD Anderson Cancer Center, Houston, TX (United States); Reynoso, F [UT MD Anderson Cancer Center, Houston, TX (United States); Washington University School of Medicine, St. Louis, MO (United States)

    2016-06-15

    Purpose: To probe physical evidences of the dose enhancement due to a low/clinically-relevant concentration of gold nanoparticles (GNPs) and Yb-169 gamma rays using PRESAGE dosimeters. Methods: A PRESAGE cuvette was placed at approximately 2 mm above the plane containing three novel Yb-169 brachytherapy seeds (3.2, 3.2, and 5.3 mCi each). Two types of PRESAGE dosimeters were used – plain PRESAGEs (controls) and PRESAGEs loaded with 0.02 wt. % of GNPs (GNP-PRESAGEs). Each PRESAGE dosimeter was irradiated with different time durations (0 to 24 hours) to deliver 0, 4, 8, 16 and 24 Gy of dose. For a reference/comparison, both types of PRESAGEs were also irradiated using 250 kVp x-rays with/without Er-filter to deliver 0, 3, 10, and 30 Gy of dose. Er-filter was used to emulate Yb-169 spectrum using 250 kVp x-rays. The absorption spectra of PRESAGEs were measured using a UV spectrophotometer and used to determine the corresponding optical densities (ODs). Results: GNP-PRESAGEs exposed to Yb-169 sources showed ∼65% increase in ODs compared with controls. When exposed to Er-filtered and unfiltered 250 kVp x-rays, they produced smaller increases in ODs, ∼41% and ∼37%, respectively. There was a linear relationship between ODs and delivered doses with a goodness-of-fit (R2) greater than 0.99. Conclusion: A notable increase in the ODs (∼65%) was observed for GNP-PRESAGEs irradiated by Yb-169 gamma rays. Considering the observed OD increases, it was highly likely that Yb-169 gamma rays were more effective than both Er-filtered and unfiltered 250 kVp x-rays, in terms of producing the dose enhancement. Due to several unknown factors (e.g., possible difference in the dose response of GNP-PRESAGEs vs. PRESAGEs), however, a further investigations is necessary to establish the feasibility of quantifying the exact amount of macroscopic or microscopic/local GNP-mediated dose enhancement using PRESAGE or similar volumetric dosimeters. Supported by DOD/PCRP grant W81XWH-12

  1. Why relevance theory is relevant for lexicography

    DEFF Research Database (Denmark)

    Bothma, Theo; Tarp, Sven

    2014-01-01

    This article starts by providing a brief summary of relevance theory in information science in relation to the function theory of lexicography, explaining the different types of relevance, viz. objective system relevance and the subjective types of relevance, i.e. topical, cognitive, situational...... that is very important for lexicography as well as for information science, viz. functional relevance. Since all lexicographic work is ultimately aimed at satisfying users’ information needs, the article then discusses why the lexicographer should take note of all these types of relevance when planning a new...... dictionary project, identifying new tasks and responsibilities of the modern lexicographer. The article furthermore discusses how relevance theory impacts on teaching dictionary culture and reference skills. By integrating insights from lexicography and information science, the article contributes to new...

  2. Deep learning relevance

    DEFF Research Database (Denmark)

    Lioma, Christina; Larsen, Birger; Petersen, Casper

    2016-01-01

    train a Recurrent Neural Network (RNN) on existing relevant information to that query. We then use the RNN to "deep learn" a single, synthetic, and we assume, relevant document for that query. We design a crowdsourcing experiment to assess how relevant the "deep learned" document is, compared...... to existing relevant documents. Users are shown a query and four wordclouds (of three existing relevant documents and our deep learned synthetic document). The synthetic document is ranked on average most relevant of all....

  3. Radiation biology. Chapter 20

    Energy Technology Data Exchange (ETDEWEB)

    Wondergem, J. [International Atomic Energy Agency, Vienna (Austria)

    2014-09-15

    Radiation biology (radiobiology) is the study of the action of ionizing radiations on living matter. This chapter gives an overview of the biological effects of ionizing radiation and discusses the physical, chemical and biological variables that affect dose response at the cellular, tissue and whole body levels at doses and dose rates relevant to diagnostic radiology.

  4. Effects of substrate concentration, specific surface area and hydraulic loading on the treatment efficiency in a submerged biological filter. Sesshoku bakkiho no shori koritsu ni taisuru kishitsu nodo, hihyo menseki oyobi suiryo fuka no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Iyo, T; Ono, S; Yoshino, T [Kitasato University, Kanagawa (Japan). School of Hygienic Science

    1991-06-10

    Effects of substrate concentration, specific surface area, and hydraulic loading, which are major factors influencing treatment efficiency in a submerged biological filter, were analyzed through the test with a special apparatus. In the test, the wall of the submerged biological filter was regarded as the contact material, and the specific surface area was changed by adjusting the sectional form of the filter. Using specimens from actual plant reservoirs, treatment efficiency for each case of three kinds of substrate concentration and hydraulic loading was measured. BOD removal rate was lower with smaller specific surface area. It was conspicuous particularly with higher BOD concentration in influent water. After the multiple regression analysis of the test results, the multiple regression equation to estimate BOD residual rate from three variates such as BOD concentration, specific surface area, and hydraulic loading was obtained. When 200mg l as BOD concentration and 50m{sup 2} m{sup {minus}3} as specific surface area were applied in this equation, the result almost agreed with the tendency obtained from data of actual plants. 6 refs., 4 figs., 1 tab.

  5. A review of biological processes within oceanic water columns relevant to the assessment of the safety of disposal of waste, notably radioactive isotopes on or within the sea bed

    International Nuclear Information System (INIS)

    Angel, M.V.

    1985-01-01

    Pelagic biological processes and their connotations in the assessment of possible dispersal mechanisms of contaminants released on the deep oceanic seabed are reviewed. Biological gradients tend to be from the surface down so the search is for processes which run counter to these general gradients. Observed profiles of standing crop of both plankton and micronekton show that below 2000 m biological activity would have to be exceptionally dynamic to have an influence that will even approach within an order of magnitude of the dispersive effect of physical mixing. Examination of all forms of known migration mechanisms fails to reveal such dynamic activity. Nor have any critical pathways been identified within the present or foreseeable pattern of exploitation of the oceans. However, a major gap in knowledge is whether the pattern of these biological processes changes substantially in the region of continental slopes. (author)

  6. Concentration of biologically active polyamines in meat and liver of sheep and lambs after slaughter and their changes in mutton during storage and cooking.

    Science.gov (United States)

    Dadáková, Eva; Pelikánová, Tamara; Kalač, Pavel

    2011-02-01

    Putrescine (PUT), spermidine (SPD) and spermine (SPM) concentrations using a UPLC method, in chilled mutton, lamb and livers 24 h after slaughter were determined. PUT concentrations were quantifiable only in some samples. Mean SPD concentrations were 4-6, 13.5 and 16.8 mg kg-1 in the meats, sheep and lamb livers, respectively. The respective SPM concentrations were 17-25, 128 and 79 mg kg-1. SPD and SPM losses of about one fifth and half of the initial level, respectively, were apparent in mutton loins stored at -18°C for 6 months. Significant losses of SPD and SPM were found in mutton loins stored aerobically, vacuum-packaged or in a modified atmosphere at +2°C. Boiling and stewing of mutton legs caused SPD and SPM losses of about 40% and roasting of about 60% of the initial content. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. Effect of Different Fertilization Systems (Chemical, Biological and Integrated( on Nitrogen and Phosphorus Concentration, Biochemical Attributes and Sepals Dry Weight of Roselle (Hibiscus sabdariffa L.

    Directory of Open Access Journals (Sweden)

    roghayeh mohammadpour vashvaei

    2017-12-01

    Full Text Available Introduction Roselle (Hibiscus sabdariffa L. is a subtropical medicinal plant belongs to the Malvaceae family. Roselle sepals are valuable due to its therapeutic properties and culinary uses. During past decades rising cost of chemical inputs and overusing them in conventional farming have caused various environmental issues such as soil and water resources contamination, reduction in food quality production, decreasing soil fertility and biological imbalance in the soil that they impose irreparable damage to ecosystems. Sustainable agriculture which is based on the use of bio-fertilizers with the aim of eliminating or considerably reducing the use of chemical inputs is the optimal solution to overcome these problems. Abo-Baker and Gehan (2011 in their study on the effect of bio-fertilizers in combination with different rates of chemical fertilizers on growth characters, yield component and chemical constituents of roselle demonstrated that the inoculation with the mixture of bio-fertilizers combined with 50 or 100% chemical fertilizers improved, in most cases, growth characters and increased sepal yield or at least did not differ significantly from the control (full recommended dose of NPK alone. These researchers stated that applying 50% of the recommended dose of NPK plus the mixture of bio-fertilizer can save half of the quantity of chemical fertilizers, decrease the production cost and obtain high quality product. The present study was designed to investigate the effect of bio-fertilizers in combination with different doses of chemical fertilizers on the element concentrations, biochemical properties and yield of roselle to find the appropriate integration of them. Material and Methods This experiment was conducted based on a randomized complete block design with three replications, at the Research Station, University of Zabol, during growing season of 2011-2012 and 2012-2013. Experimental treatments were plant nutrition with NPK (220, 130

  8. Up-regulation of visfatin expression in subjects with hyperthyroidism and hypothyroidism is partially relevant to a nonlinear regulation mechanism between visfatin and tri-iodothyronine with various concentrations.

    Science.gov (United States)

    Han, Jing; Zhang, Tian-ou; Xiao, Wen-hua; Chang, Cui-qing; Ai, Hua

    2012-03-01

    Visfatin, a visceral fat-derived adipocytokine, plays a significant physiological function in lipid metabolism. However, the precise function of visfatin and its regulation by thyroid hormones are still unknown. This study observed the plasma visfatin concentrations in subjects with hyperthyroidism and hypothyroidism in vivo, and investigated the possible regulation mechanism between visfatin and tri-iodothyronine (T3) in vitro as a further interpretation. The experiment in vivo included clinical subjects (57 patients with thyroid dysfunction and 29 euthyroid healthy volunteers) and an animal model (24 Wistar rats). All subjects were divided into hyperthyroidism, hypothyroidism and euthyroidism groups, with plasma thyroid hormones, thyrotropin, visfatin and triglyceride concentrations determined. Visfatin mRNA expression in visceral fat and liver of rats was detected by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR). The experiment in vitro studied 3T3-L1 cells and visfatin mRNA expression under nine different T3 concentrations (0, 0.1, 0.25, 0.5, 1, 5, 10, 20, 100 nmol/L) using quantitative real-time RT-PCR. Clinical subjects and animal models showed elevated plasma visfatin concentrations in the hyperthyroidism group (20.466 ng/ml (15.263, 26.795 ng/ml) and (1209.164±165.292) ng/L) and hypothyroidism group (12.457 ng/ml (11.115, 15.454 ng/ml) and (1205.425±109.200) ng/L) compared to euthyroidism group (6.891 ng/ml (5.888, 8.803 ng/ml) and (926.650±54.002) ng/L, Phyperthyroidism and hypothyroidism groups increased about 3.33-fold and 1.98-fold compared to the euthyroidism group (P0.05) and correlation (r=0.121, P=0.572) was found in the liver. T3 induced a remarkable increase of visfatin mRNA expression in 3T3-L1 cells at low concentrations (0-0.5 nmol/L T3) followed by a sharp decrease at higher concentrations (0.5-100 nmol/L T3), with an inflection point at 0.5 nmol/L T3. Elevated circulating visfatin levels in subjects with

  9. Autopsy tissues as biological monitors of human exposure to environmental pollutants. A case study: Concentrations of metals and PCDD/Fs in subjects living near a hazardous waste incinerator.

    Science.gov (United States)

    Domingo, José L; García, Francisco; Nadal, Martí; Schuhmacher, Marta

    2017-04-01

    Human biomonitoring is of tremendous importance to prevent potential adverse effects derived from human exposure to chemicals. Blood and urine are among the biological monitors more frequently used. However, biological matrices such as breast milk, hair, nails, saliva, feces, teeth, and expired air are also often used. In addition, and focused mainly on long-term exposure, adipose tissue and other human tissues like bone, liver, brain or kidney, are also used as biological monitors of certain substances, especially for long-term biomonitoring. However, for this kind of tissues sampling is always a limiting factor. In this paper, we have examined the role of autopsy tissues as biological monitors of human exposure to environmental pollutants. For it, we have used a case study conducted near a hazardous waste incinerator (HWI) in Catalonia (Spain), in which the concentrations of metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), have been periodically determined in autopsy tissues of subjects living in the area under potential influence of the facility. This case study does not show advantages -in comparison to other appropriate biomonitors such as blood- in using autopsy tissues in the monitoring of long-term exposure to metals and PCDD/Fs. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. ESR low-temperature investigations on water-containing biological substances to determine type, concentration and kinetics of the free radicals induced by irradiation with X-rays and β-radiation

    International Nuclear Information System (INIS)

    Fell, H.A.

    1975-01-01

    In the present work, ESR investigations on pure water and further biological interesting substances with high water content were carried out. In order to stabilize the free primary radicals occurring after irradiation, it was necessary to cool down the samples to the temperature of liquid helium. Methods were developed which enabled irradiation of the pure sample substance at this temperature to be performed. Two different kinds of radiation were applied, X-ray and β-radiation, and the results were compared with one another. The problem of transporting the irradiated sample from the place of irradiation to the measuring position maintaining 4.2 K was solved. A device was constructed to study the radical kinetics with whose assistance the samples can be brought to a pre-chosen temperature for a certain time. A calibration of the ESR spectrometer as well as the use of a secondary standard was necessary for the quantitative determination of the radical concentration. The type and concentration of the primary radicals occurring were investigated in the measured samples as well as the reduction of the radical concentration with increasing temperature determined. The measured values were compared with theoretical considerations. The effect of the radicals on biological systems at various temperatures was discussed. (orig./LH) [de

  11. Seasonal and biological variation of blood concentrations of total cholesterol, dehydroepiandrosterone sulfate, hemoglobin A(1c), IgA, prolactin, and free testosterone in healthy women

    DEFF Research Database (Denmark)

    Garde, A H; Hansen, Åse Marie; Skovgaard, L T

    2000-01-01

    Concentrations of physiological response variables fluctuate over time. The present study describes within-day and seasonal fluctuations for total cholesterol, dehydroepiandrosterone sulfate (DHEA-S), hemoglobin A(1c) (HbA(1c)), IgA, prolactin, and free testosterone in blood, and estimates within......- (CV(i)) and between-subject (CV(g)) CVs for healthy women. In addition, the index of individuality, prediction intervals, and power calculations were derived....

  12. Impact of Biological Feedback and Incentives on Blood Fatty Acid Concentrations, Including Omega-3 Index, in an Employer-Based Wellness Program.

    Science.gov (United States)

    McBurney, Michael I; Bird, Julia K

    2017-08-05

    Eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic acid (DHA, C22:6n-3) are important fatty acids for the retina and brain. More than 95% of Americans have suboptimal EPA + DHA blood concentrations. This cross-sectional employer-based study assessed whole blood fatty acid levels of volunteers participating in an onsite wellness biometric screening program and was designed to determine if an incentive, a $5 coupon for a 90-day supply of fish oil supplement typically costing $18-30, stimulated incremental dietary behavior change relative to nutritional status assessment alone to increase EPA + DHA concentrations. Volunteers completed a dietary survey and finger stick blood samples were collected to be analyzed for fatty acid composition. In addition, 636 individuals participated in the initial onsite biometric screening. Three months later, and without prior knowledge, all employees were invited to a second screening. At the second screening, 198 employees volunteered for the first time and 149 employees had a second test (17.9%). At baseline, the average age ( n = 834) was 45 year and omega-3 index was 5.0% with 41% female. EPA + DHA concentration, i.e., omega-3 index, was significantly lower in men (4.8%) than women (5.2%), as were DHA and linoleic acid (LA) concentrations ( p omega-3 index was positively and linearly associated with omega-3 intake. Only 4% of volunteers had an omega-3 index >8% on initial screening. Among the 149 individuals with two measurements, omega-3 intake from supplements, but not food, increased significantly from 258 to 445 mg/d ( p omega-3 index (+0.21, p omega-3 supplement.

  13. Impact of Biological Feedback and Incentives on Blood Fatty Acid Concentrations, Including Omega-3 Index, in an Employer-Based Wellness Program

    Directory of Open Access Journals (Sweden)

    Michael I. McBurney

    2017-08-01

    Full Text Available Eicosapentaenoic acid (EPA, C20:5n-3 and docosahexaenoic acid (DHA, C22:6n-3 are important fatty acids for the retina and brain. More than 95% of Americans have suboptimal EPA + DHA blood concentrations. This cross-sectional employer-based study assessed whole blood fatty acid levels of volunteers participating in an onsite wellness biometric screening program and was designed to determine if an incentive, a $5 coupon for a 90-day supply of fish oil supplement typically costing $18–30, stimulated incremental dietary behavior change relative to nutritional status assessment alone to increase EPA + DHA concentrations. Volunteers completed a dietary survey and finger stick blood samples were collected to be analyzed for fatty acid composition. In addition, 636 individuals participated in the initial onsite biometric screening. Three months later, and without prior knowledge, all employees were invited to a second screening. At the second screening, 198 employees volunteered for the first time and 149 employees had a second test (17.9%. At baseline, the average age (n = 834 was 45 year and omega-3 index was 5.0% with 41% female. EPA + DHA concentration, i.e., omega-3 index, was significantly lower in men (4.8% than women (5.2%, as were DHA and linoleic acid (LA concentrations (p < 0.05. Baseline omega-3 index was positively and linearly associated with omega-3 intake. Only 4% of volunteers had an omega-3 index >8% on initial screening. Among the 149 individuals with two measurements, omega-3 intake from supplements, but not food, increased significantly from 258 to 445 mg/d (p < 0.01 at the second test as did the omega-3 index (+0.21, p < 0.02. In this employed population, only 1% redeemed a coupon for an omega-3 supplement.

  14. WE-H-BRA-09: Application of a Modified Microdosimetric-Kinetic Model to Analyze Relative Biological Effectiveness of Ions Relevant to Light Ion Therapy Using the Particle Heavy Ion Transport System

    Energy Technology Data Exchange (ETDEWEB)

    Butkus, M [Yale-New Haven Hospital, New Haven, CT (United States); Palmer, T [Oregon State University, Corvallis, OR (United States)

    2016-06-15

    Purpose: To evaluate the dose and biological effectiveness of various ions that could potentially be used for actively scanned particle therapy. Methods: The PHITS Monte Carlo code paired with a microscopic analytical function was used to determine probability distribution functions of the lineal energy in 0.3µm diameter spheres throughout a water phantom. Twenty million primary particles for 1H beams and ten million particles for 4He, 7Li, 10B, 12C, 14N, 16O, and 20Ne were simulated for 0.6cm diameter pencil beams. Beam energies corresponding to Bragg peak depths of 50, 100, 150, 200, 250, and 300mm were used and evaluated transversely every millimeter and radially in annuli with outer radius of 1.0, 2.0, 3.0, 3.2, 3.4, 3.6, 4.0, 5.0, 10.0, 15.0, 20.0 and 25.0mm. The acquired probability distributions were reduced to dose-mean lineal energies and applied to the modified microdosimetric kinetic model for five different cell types to calculate relative biological effectiveness (RBE) compared to 60Co beams at the 10% survival threshold. The product of the calculated RBEs and the simulated physical dose was taken to create biological dose and comparisons were then made between the various ions. Results: Transversely, the 10B beam was seen to minimize relative biological dose in both the constant and accelerated dose change regions, proximal to the Bragg Peak, for all beams traveling greater than 50mm. For the 50mm beam, 7Li was seen to provide the most optimal biological dose profile. Radially small fluctuations (<4.2%) were seen in RBE while physical dose was greater than 1% for all beams. Conclusion: Even with the growing usage of 12C, it may not be the most optimal ion in all clinical situations. Boron was calculated to have slightly enhanced RBE characteristics, leading to lower relative biological doses.

  15. Monitoring of total metal concentration in sludge samples: Case study for the mechanical–biological wastewater treatment plant in Velika Gorica, Croatia

    International Nuclear Information System (INIS)

    Filipović, Josip; Grčić, Ivana; Bermanec, Vladimir; Kniewald, Goran

    2013-01-01

    In this paper, monitoring of total metal concentration in sludge samples from wastewater treatment process is elaborated. The presented results summarize the analyses of sludge samples in a period from 2008 to 2012. Possible sources of pollutions are given. Primarily, waste solid samples were collected from different pretreatment steps: (A) coarse grid, (B) fine grid and (C) aerated sand grease grid. Samples of A and B followed a repeatable pattern in 2008 and 2010. According to the results from 2008, samples of C contained measurable concentration of the following metals (mg/kg dry matter): Zn (21), Ni (1.05) and Ba (14.9). Several types of sludge samples were analyzed: fresh raw sludge (PS; 6–12 hour old), the sludge from the digester for anaerobic sludge treatment (DS; 48–72 hour old), samples from lagoons where the sludge is temporarily deposited (DOS and DOSold; 30–120 days) and sludge samples from agricultural areas (AA; aged over 180 days). Additionally, samples of dehydrated sludge (DEHS and DEHSold; 90–180 days) were collected upon construction of equipment for sludge dehydration in 2011. An analysis of total metal concentrations for Cu, Zn, Cr, Pb, Ni, Hg, Cd, Ba, As, Se, Sb, Co, Mo, Fe and Mn was performed by flame atomic absorption spectrometry (FAAS) and inductively coupled plasma-optical emission spectrometry (ICP-OES). The most recent results (year 2011) indicated a high concentration of heavy metals in PS samples, exceeding the MCLs (mg/kg dry matter): Cu (2122), Zn (5945), Hg (13.67) and Cd (6.29). In 2012 (until July), only a concentration of Cu exceeded MCL (928.75 and 1230.5 in DS and DEHS, respectively). A composition of sludge was variable through time, offering the limited possibility for future prediction. The sludge is being considered as a hazardous waste and a subject of discussion regarding disposal. - Highlights: ► Summarized 5-year monitoring data for heavy metals in sludge ► Partially determined sources of pollution by

  16. Study of the correlation between the concentration of potassium in an extract of Aferontany and its biological effect on an isolated heart

    International Nuclear Information System (INIS)

    MANOELA, F.P.

    2005-01-01

    The objective of the present work is to determine the elemental quality of the extract of the malagasy medicinal plant, named Aferontany (Mollugo Nudicaulis), in particular the content of potassium in order to measure its contribution to cause heart hazardous. Decoction was used for plant extraction purposes. Total Refection X ray fluorescence analytical method was employed for the quantitative analysis. Organ isolated test method was applied to evaluate the impact of potassium in the extract on heart. The analytical results showed that Aferontany plant contains potassium (K), calcium (Ca), iron (Fe), titanium (Ti), zinc (Zn), manganese (Mn), rubidium (Rb), barium (Ba), strontium (Sr), copper (Cu) and lead (Pb).Their concentration varies with the collecting sites, the conservation duration, the age and the type of plant used organ. The potassium content of the plant is high and varies between 0.016 and 0.064%. The obtained results showed that the elemental concentrations in the decoction increase with the amount of used plant, the temperature and the duration. The concentration value of strontium is lower than 14 μg/L (MDL). The toxic elements concentrations measured in the decoction are low and in the order of 160 μg/L, 6.45 μg/L for the barium and the lead respectively (1g of decocted plant for 100 mL of water). The same decoction contains 5.59 mg/L of calcium, 346 μg/L of manganese 4.05 mg/L of Iron and 130 μg/L of copper. When using the ordinary posology, these elements do not present theoretically any problem on heart function. Besides, the decoction has 520 mg/L of potassium. This high content of potassium may cause heart problem. According to the experimentation carried out on the frog heart, cardiac stopping may occur if the potassium concentration value is in the order of 1100 mg/L. Therefore, The plant decoction would have mortal effect in the case of over uptake. Nevertheless, the intoxication is reversible [fr

  17. Monitoring of total metal concentration in sludge samples: Case study for the mechanical–biological wastewater treatment plant in Velika Gorica, Croatia

    Energy Technology Data Exchange (ETDEWEB)

    Filipović, Josip [Town Office for Physical Planning and Environmental Protection, Velika Gorica County, Trg kralja Tomislava 34, 10410 Velika Gorica (Croatia); Grčić, Ivana, E-mail: igrcic@fkit.hr [Faculty of Chemical Engineering and Technology, University of Zagreb Marulićev trg 19, 10000 Zagreb (Croatia); Bermanec, Vladimir [Institute of Mineralogy and Petrology, Faculty of Science, University of Zagreb, Horvatovac bb, 10000 Zagreb (Croatia); Kniewald, Goran [Division for Marine and Environmental Research, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb (Croatia)

    2013-03-01

    In this paper, monitoring of total metal concentration in sludge samples from wastewater treatment process is elaborated. The presented results summarize the analyses of sludge samples in a period from 2008 to 2012. Possible sources of pollutions are given. Primarily, waste solid samples were collected from different pretreatment steps: (A) coarse grid, (B) fine grid and (C) aerated sand grease grid. Samples of A and B followed a repeatable pattern in 2008 and 2010. According to the results from 2008, samples of C contained measurable concentration of the following metals (mg/kg dry matter): Zn (21), Ni (1.05) and Ba (14.9). Several types of sludge samples were analyzed: fresh raw sludge (PS; 6–12 hour old), the sludge from the digester for anaerobic sludge treatment (DS; 48–72 hour old), samples from lagoons where the sludge is temporarily deposited (DOS and DOSold; 30–120 days) and sludge samples from agricultural areas (AA; aged over 180 days). Additionally, samples of dehydrated sludge (DEHS and DEHSold; 90–180 days) were collected upon construction of equipment for sludge dehydration in 2011. An analysis of total metal concentrations for Cu, Zn, Cr, Pb, Ni, Hg, Cd, Ba, As, Se, Sb, Co, Mo, Fe and Mn was performed by flame atomic absorption spectrometry (FAAS) and inductively coupled plasma-optical emission spectrometry (ICP-OES). The most recent results (year 2011) indicated a high concentration of heavy metals in PS samples, exceeding the MCLs (mg/kg dry matter): Cu (2122), Zn (5945), Hg (13.67) and Cd (6.29). In 2012 (until July), only a concentration of Cu exceeded MCL (928.75 and 1230.5 in DS and DEHS, respectively). A composition of sludge was variable through time, offering the limited possibility for future prediction. The sludge is being considered as a hazardous waste and a subject of discussion regarding disposal. - Highlights: ► Summarized 5-year monitoring data for heavy metals in sludge ► Partially determined sources of pollution by

  18. Effects of glycerol upon the biological actions of near-ultraviolet light: spectra and concentration dependence for transforming DNA and for Escherichia coli B/r

    International Nuclear Information System (INIS)

    Peak, J.G.; Peak, M.J.; Foote, C.S.

    1982-01-01

    The concentration dependence for the protection of isolated transforming DNA and Escherichia coli by glycerol against 365-nm monochromatic near-ultraviolet light (UV) was measured. Glycerol protection saturates at a concentration of about 0.1 M for DNA and 1.0 M for E. coli. Action spectra for glycerol protection of transforming DNA (tryptophan and histidine markers) are similar to those obtained previously for diazobicyclo[2.2.2.]octane (DABCO) protection, with protection reaching a maximum near 350-nm UV and decreasing rapidly at wavelengths above and below 350 nm. However, glycerol protects against near-UV about twice as efficiently as DABCO. The action spectrum for protection of E. coli by glycerol against the lethal effects of near-UV was not the same as the spectrum for DNA since glycerol sensitized the cells, but not the DNA, at wavelengths longer than about 380 nm. A possible role of hydroxyl or other radicals was supported by the observation that benzoate also protected DNA against inactivation by 334-nm UV. (author)

  19. 2004 list of MAK (maximum work place concentration) and BAT (biological workplace tolerance) values; MAK- und BAT-Werte-Liste 2004

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    The MAK value (maximum workplace concentration) is the highest permissible concentration of a working material occurring in the ambient air of the workplace as a gas or vapour or in suspended form which according to the present state of knowledge does not, in general, impair the health of or pose an unreasonable molestation (for example through repulsive odour) to employees even in the case of repeated, long-term exposure, that is as a rule 8 hours daily, assuming an average working week of no more than 40 hours. As a rule, MAK values are quoted as average values over a time period of up to one working day or shift. They are primarily defined in consideration of effect characteristics of the substances in question, but also - as far as possible - of the practical conditions attending the work processes or the exposure patterns which they entail. This is done on the basis of scientifically founded criteria of health protection, not on whether providing such protection is technically or economically feasible. In addition, substances are assessed in terms of carcinogenicity, sensitising effects, any contribution to systemic toxicity following cutaneous resorption, hazards for pregnancy and germ cell mutagenicity and are classified or marked accordingly. The Commission's procedures in assessing substances with respect to these criteria are described in corresponding sections of the MAK and BAT list of values, in the ''Toxicological and occupational medical explanations of MAK values'' and in scientific journals.

  20. The impact of furfural concentrations and substrate-to-biomass ratios on biological hydrogen production from synthetic lignocellulosic hydrolysate using mesophilic anaerobic digester sludge.

    Science.gov (United States)

    Akobi, Chinaza; Hafez, Hisham; Nakhla, George

    2016-12-01

    This study evaluated the impact of furfural (a furan derivative) on hydrogen production rates and yields at initial substrate-to-microorganism ratios (S°/X°) of 4, 2, 1, and 0.5gCOD/gVSS and furfural concentrations of 4, 2, 1, and 0.5g/L. Fermentation studies were carried out in batches using synthetic lignocellulosic hydrolysate as substrate and mesophilic anaerobic digester sludge as seed. Contrary to other literature studies where furfural was inhibitory, this study showed that furfural concentrations of up to 1g/L enhanced hydrogen production with yields as high as 19% from the control (batch without furfural). Plots of hydrogen yields against gfurfural/gsugars and hydrogen yields versus gfurfural/gbiomass showed negative linear correlation indicating that these parameters influence biohydrogen production. Regression analysis indicated that gfurfural/gsugars initial exerted a greater effect on the degree of inhibition of hydrogen production than gfurfural/gVSS final . Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Effects of temperature, plant configuration and loading on the effluent concentration of biological sewage treatment plants; Einfluss von Temperatur, Anlagenkonfiguration und Auslastung auf die Ablaufkonzentration bei der biologischen Abwasserreinigung

    Energy Technology Data Exchange (ETDEWEB)

    Durth, A.

    2000-07-01

    The design of wastewater treatment plants is generally based on the maximum growth rate of the nitrifiers, which is smaller and shows a stronger dependency on temperature than the growth rate of heterotrophic bacteria. This 'kinetic temperature influence' is usually described by exponential equations with a temperature coefficient {theta}. Using these equations for the design of treatment plants results in large volumes of the aeration basin, followed by high investment cost and consumption of large space. On the other hand, long-term effluent data from various plants reveal a small or even no temperature influence on the effluent concentrations. This effect has to be attributed to other influences, which can only be taken into account by modelling the process as a whole. Therefore, the aim of this thesis is to quantify the temperature influence on the effluent concentration of biological treatment by modelling the entire treatment process. (orig.)

  2. Determination of trace aluminum concentration and homogeneity in biological material TORT-1 by instrumental neutron activation and graphite furnace atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Kratochvil, B.; Motkosky, N.; Duke, M.J.M.; Ng, D.

    1987-01-01

    The biological reference material TORT-1, lobster hepatopancreas, was analyzed for aluminum by instrumental neutron activation analysis (INAA) and graphite furnace atomic absorption spectroscopy (GFAAS). After correction of the INAA results for interferences from 28 Al produced by 31 P(n,α) 28 Al and 28 (n,p) 28 Al reactions, and use of HNO 3 plus HF for sample dissolution for the GFAAS analyses, the methods gave similar results of 43 ± 3 and 42 ± 2 μg/g respectively for 200 to 300-mg test portions. Analysis of six portions from each of six bottles of TORT-1 showed no statistical difference at the 95% confidence level for the between and within bottle variances. Therefore, The material can be considered homogeneous for aluminum if 200- to 300-mg test portions are taken. The variance was greater and the average lower when 30-mg test portions were analyzed for aluminum by GFAAS. The pattern of the results, together with the need for HF in the dissolution procedure, suggests the presence of aluminum-containing microparticulate mineral matter, perhaps silicate material, in the material

  3. Determination of trace aluminum concentration and homogeneity in biological material TORT-1 by instrumental neutron activation and graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Kratochvil, B; Motkosky, N; Duke, M J.M.; Ng, D

    1987-05-01

    The biological reference material TORT-1, lobster hepatopancreas, was analyzed for aluminum by instrumental neutron activation analysis (INAA) and graphite furnace atomic absorption spectroscopy (GFAAS). After correction of the INAA results for interferences from /sup 28/Al produced by /sup 31/P(n,..cap alpha..)/sup 28/Al and /sup 28/(n,p)/sup 28/Al reactions, and use of HNO/sub 3/ plus HF for sample dissolution for the GFAAS analyses, the methods gave similar results of 43 +- 3 and 42 +- 2 ..mu..g/g respectively for 200 to 300-mg test portions. Analysis of six portions from each of six bottles of TORT-1 showed no statistical difference at the 95% confidence level for the between and within bottle variances. Therefore, The material can be considered homogeneous for aluminum if 200- to 300-mg test portions are taken. The variance was greater and the average lower when 30-mg test portions were analyzed for aluminum by GFAAS. The pattern of the results, together with the need for HF in the dissolution procedure, suggests the presence of aluminum-containing microparticulate mineral matter, perhaps silicate material, in the material.

  4. Some nonlinear challenges in biology

    International Nuclear Information System (INIS)

    Mosconi, Francesco; Julou, Thomas; Desprat, Nicolas; Sinha, Deepak Kumar; Allemand, Jean-François; Croquette, Vincent; Bensimon, David

    2008-01-01

    Driven by a deluge of data, biology is undergoing a transition to a more quantitative science. Making sense of the data, building new models, asking the right questions and designing smart experiments to answer them are becoming ever more relevant. In this endeavour, nonlinear approaches can play a fundamental role. The biochemical reactions that underlie life are very often nonlinear. The functional features exhibited by biological systems at all levels (from the activity of an enzyme to the organization of a colony of ants, via the development of an organism or a functional module like the one responsible for chemotaxis in bacteria) are dynamically robust. They are often unaffected by order of magnitude variations in the dynamical parameters, in the number or concentrations of actors (molecules, cells, organisms) or external inputs (food, temperature, pH, etc). This type of structural robustness is also a common feature of nonlinear systems, exemplified by the fundamental role played by dynamical fixed points and attractors and by the use of generic equations (logistic map, Fisher–Kolmogorov equation, the Stefan problem, etc.) in the study of a plethora of nonlinear phenomena. However, biological systems differ from these examples in two important ways: the intrinsic stochasticity arising from the often very small number of actors and the role played by evolution. On an evolutionary time scale, nothing in biology is frozen. The systems observed today have evolved from solutions adopted in the past and they will have to adapt in response to future conditions. The evolvability of biological system uniquely characterizes them and is central to biology. As the great biologist T Dobzhansky once wrote: 'nothing in biology makes sense except in the light of evolution'. (open problem)

  5. Effect of TiO2 Nanofiller Concentration on the Mechanical, Thermal and Biological Properties of HDPE/TiO2 Nanocomposites

    Science.gov (United States)

    Mozumder, Mohammad Sayem; Mourad, Abdel-Hamid I.; Mairpady, Anusha; Pervez, Hifsa; Haque, Md Emdadul

    2018-05-01

    The necessity for advanced and effective biomimetic tissue engineering materials has increased massively as bone diseases such as osteoporosis and bone cancer have become a major public health problem. Therefore, the objective of this study is to develop titanium dioxide (TiO2) nanoparticles-enriched high-density polyethylene (HDPE) nanocomposites that could serve as potential biomaterials. HDPE/TiO2 nanocomposites with varying TiO2 nanoparticles content were fabricated by using injection molding technique and were subjected to mechanical, thermal and biological characterization. SEM-EDS analysis confirmed even dispersion of TiO2 nanoparticles into the HDPE matrix. It was observed from the mechanical testing that the addition of TiO2 nanoparticles to HDPE noticeably improved the stiffness (from 345 to 378 MPa) while maintaining almost similar yield strength of pure HDPE. The thermal analyses revealed that TiO2 nanoparticles inclusion to HDPE matrix enhanced the thermal stability of nanocomposites, as the overall rate of crystallization increased by almost 4%. Furthermore, biocompatibility of nanocomposites was also studied by means of various cell culture experiments; human osteoblasts (hFOB) were seeded on the HDPE/TiO2 nanocomposites and were visualized through SEM after 72 h of incubation; surface morphology revealed normal cell growth and spreading with more attachment on PNC-10 that contains 10 wt.% of TiO2. Moreover, cell viability assays (i.e., MTT and cell attachment) revealed consistent increase in cell count and metabolic activity when triplicate cultures were incubated for 1, 3 and 7 days.

  6. Effect of TiO2 Nanofiller Concentration on the Mechanical, Thermal and Biological Properties of HDPE/TiO2 Nanocomposites

    Science.gov (United States)

    Mozumder, Mohammad Sayem; Mourad, Abdel-Hamid I.; Mairpady, Anusha; Pervez, Hifsa; Haque, Md Emdadul

    2018-03-01

    The necessity for advanced and effective biomimetic tissue engineering materials has increased massively as bone diseases such as osteoporosis and bone cancer have become a major public health problem. Therefore, the objective of this study is to develop titanium dioxide (TiO2) nanoparticles-enriched high-density polyethylene (HDPE) nanocomposites that could serve as potential biomaterials. HDPE/TiO2 nanocomposites with varying TiO2 nanoparticles content were fabricated by using injection molding technique and were subjected to mechanical, thermal and biological characterization. SEM-EDS analysis confirmed even dispersion of TiO2 nanoparticles into the HDPE matrix. It was observed from the mechanical testing that the addition of TiO2 nanoparticles to HDPE noticeably improved the stiffness (from 345 to 378 MPa) while maintaining almost similar yield strength of pure HDPE. The thermal analyses revealed that TiO2 nanoparticles inclusion to HDPE matrix enhanced the thermal stability of nanocomposites, as the overall rate of crystallization increased by almost 4%. Furthermore, biocompatibility of nanocomposites was also studied by means of various cell culture experiments; human osteoblasts (hFOB) were seeded on the HDPE/TiO2 nanocomposites and were visualized through SEM after 72 h of incubation; surface morphology revealed normal cell growth and spreading with more attachment on PNC-10 that contains 10 wt.% of TiO2. Moreover, cell viability assays (i.e., MTT and cell attachment) revealed consistent increase in cell count and metabolic activity when triplicate cultures were incubated for 1, 3 and 7 days.

  7. Making Deferred Taxes Relevant

    NARCIS (Netherlands)

    Brouwer, Arjan; Naarding, Ewout

    2018-01-01

    We analyse the conceptual problems in current accounting for deferred taxes and provide solutions derived from the literature in order to make International Financial Reporting Standards (IFRS) deferred tax numbers value-relevant. In our view, the empirical results concerning the value relevance of

  8. Parsimonious relevance models

    NARCIS (Netherlands)

    Meij, E.; Weerkamp, W.; Balog, K.; de Rijke, M.; Myang, S.-H.; Oard, D.W.; Sebastiani, F.; Chua, T.-S.; Leong, M.-K.

    2008-01-01

    We describe a method for applying parsimonious language models to re-estimate the term probabilities assigned by relevance models. We apply our method to six topic sets from test collections in five different genres. Our parsimonious relevance models (i) improve retrieval effectiveness in terms of

  9. Effect of sample preparation techniques on the concentrations and distributions of elements in biological tissues using µSRXRF: a comparative study

    International Nuclear Information System (INIS)

    Al-Ebraheem, A; Dao, E; Desouza, E; McNeill, F E; Farquharson, M J; Li, C; Wainman, B C

    2015-01-01

    Routine tissue sample preparation using chemical fixatives is known to preserve the morphology of the tissue being studied. A competitive method, cryofixation followed by freeze drying, involves no chemical agents and maintains the biological function of the tissue. The possible effects of both sample preparation techniques in terms of the distribution of bio-metals (calcium (Ca), copper (Cu) zinc (Zn), and iron (Fe) specifically) in human skin tissue samples was investigated. Micro synchrotron radiation x-ray fluorescence (μSRXRF) was used to map bio-metal distribution in epidermal and dermal layers of human skin samples from various locations of the body that have been prepared using both techniques. For Ca, Cu and Zn, there were statistically significant differences between the epidermis and dermis using the freeze drying technique (p = 0.02, p < 0.01, and p < 0.01, respectively). Also using the formalin fixed, paraffin embedded technique the levels of Ca, Cu and Zn, were significantly different between the epidermis and dermis layers (p = 0.03, p < 0.01, and p < 0.01, respectively). However, the difference in levels of Fe between the epidermis and dermis was unclear and further analysis was required. The epidermis was further divided into two sub-layers, one mainly composed of the stratum corneum and the other deeper layer, the stratum basale. It was found that the difference between the distribution of Fe in the two epidermal layers using the freeze drying technique resulted in a statistically significant difference (p = 0.012). This same region also showed a difference in Fe using the formalin fixed, paraffin embedded technique (p < 0.01). The formalin fixed, paraffin embedded technique also showed a difference between the deeper epidermal layer and the dermis (p < 0.01). It can be concluded that studies involving Ca, Cu and Zn might show similar results using both sample preparation techniques, however studies involving Fe would need more

  10. Mexico City normal weight children exposed to high concentrations of ambient PM2.5 show high blood leptin and endothelin-1, vitamin D deficiency, and food reward hormone dysregulation versus low pollution controls. Relevance for obesity and Alzheimer disease.

    Science.gov (United States)

    Calderón-Garcidueñas, Lilian; Franco-Lira, Maricela; D'Angiulli, Amedeo; Rodríguez-Díaz, Joel; Blaurock-Busch, Eleonore; Busch, Yvette; Chao, Chih-kai; Thompson, Charles; Mukherjee, Partha S; Torres-Jardón, Ricardo; Perry, George

    2015-07-01

    Millions of Mexico, US and across the world children are overweight and obese. Exposure to fossil-fuel combustion sources increases the risk for obesity and diabetes, while long-term exposure to fine particulate matter (PM2.5) and ozone (O3) above US EPA standards is associated with increased risk of Alzheimer's disease (AD). Mexico City Metropolitan Area children are chronically exposed to PM2.5 and O3 concentrations above the standards and exhibit systemic, brain and intrathecal inflammation, cognitive deficits, and Alzheimer disease neuropathology. We investigated adipokines, food reward hormones, endothelial dysfunction, vitamin D and apolipoprotein E (APOE) relationships in 80 healthy, normal weight 11.1±3.2 year olds matched by age, gender, BMI and SES, low (n: 26) versus high (n:54) PM2.5 exposures. Mexico City children had higher leptin and endothelin-1 (pMexico City APOE 4 versus 3 children had higher glucose (p=0.009). Serum 25-hydroxyvitamin DMexico City children. Leptin is strongly positively associated to PM 2.5 cumulative exposures. Residing in a high PM2.5 and O3 environment is associated with 12h fasting hyperleptinemia, altered appetite-regulating peptides, vitamin D deficiency, and increases in ET-1 in clinically healthy children. These changes could signal the future trajectory of urban children towards the development of insulin resistance, obesity, type II diabetes, premature cardiovascular disease, addiction-like behavior, cognitive impairment and Alzheimer's disease. Increased efforts should be made to decrease pediatric PM2.5 exposures, to deliver health interventions prior to the development of obesity and to identify and mitigate environmental factors influencing obesity and Alzheimer disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Possibility of Predicting Serotonin Transporter Occupancy From the In Vitro Inhibition Constant for Serotonin Transporter, the Clinically Relevant Plasma Concentration of Unbound Drugs, and Their Profiles for Substrates of Transporters.

    Science.gov (United States)

    Yahata, Masahiro; Chiba, Koji; Watanabe, Takao; Sugiyama, Yuichi

    2017-09-01

    Accurate prediction of target occupancy facilitates central nervous system drug development. In this review, we discuss the predictability of serotonin transporter (SERT) occupancy in human brain estimated from in vitro K i values for human SERT and plasma concentrations of unbound drug (C u,plasma ), as well as the impact of drug transporters in the blood-brain barrier. First, the geometric means of in vitro K i values were compared with the means of in vivo K i values (K i,u,plasma ) which were calculated as C u,plasma values at 50% occupancy of SERT obtained from previous clinical positron emission tomography/single photon emission computed tomography imaging studies for 6 selective serotonin transporter reuptake inhibitors and 3 serotonin norepinephrine reuptake inhibitors. The in vitro K i values for 7 drugs were comparable to their in vivo K i,u,plasma values within 3-fold difference. SERT occupancy was overestimated for 5 drugs (P-glycoprotein substrates) and underestimated for 2 drugs (presumably uptake transporter substrates, although no evidence exists as yet). In conclusion, prediction of human SERT occupancy from in vitro K i values and C u,plasma was successful for drugs that are not transporter substrates and will become possible in future even for transporter substrates, once the transporter activities will be accurately estimated from in vitro experiments. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  12. Anion binding in biological systems

    Energy Technology Data Exchange (ETDEWEB)

    Feiters, Martin C [Department of Organic Chemistry, Institute for Molecules and Materials, Faculty of Science, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen (Netherlands); Meyer-Klaucke, Wolfram [EMBL Hamburg Outstation at DESY, Notkestrasse 85, D-22607 Hamburg (Germany); Kostenko, Alexander V; Soldatov, Alexander V [Faculty of Physics, Southern Federal University, Sorge 5, Rostov-na-Donu, 344090 (Russian Federation); Leblanc, Catherine; Michel, Gurvan; Potin, Philippe [Centre National de la Recherche Scientifique and Universite Pierre et Marie Curie Paris-VI, Station Biologique de Roscoff, Place Georges Teissier, BP 74, F-29682 Roscoff cedex, Bretagne (France); Kuepper, Frithjof C [Scottish Association for Marine Science, Dunstaffnage Marine Laboratory, Oban, Argyll PA37 1QA, Scotland (United Kingdom); Hollenstein, Kaspar; Locher, Kaspar P [Institute of Molecular Biology and Biophysics, ETH Zuerich, Schafmattstrasse 20, Zuerich, 8093 (Switzerland); Bevers, Loes E; Hagedoorn, Peter-Leon; Hagen, Wilfred R, E-mail: m.feiters@science.ru.n [Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft (Netherlands)

    2009-11-15

    We compare aspects of biological X-ray absorption spectroscopy (XAS) studies of cations and anions, and report on some examples of anion binding in biological systems. Brown algae such as Laminaria digitata (oarweed) are effective accumulators of I from seawater, with tissue concentrations exceeding 50 mM, and the vanadate-containing enzyme haloperoxidase is implicated in halide accumulation. We have studied the chemical state of iodine and its biological role in Laminaria at the I K edge, and bromoperoxidase from Ascophyllum nodosum (knotted wrack) at the Br K edge. Mo is essential for many forms of life; W only for certain archaea, such as Archaeoglobus fulgidus and the hyperthermophilic archaeon Pyrococcus furiosus, and some bacteria. The metals are bound and transported as their oxo-anions, molybdate and tungstate, which are similar in size. The transport protein WtpA from P. furiosus binds tungstate more strongly than molybdate, and is related in sequence to Archaeoglobus fulgidus ModA, of which a crystal structure is known. We have measured A. fulgidus ModA with tungstate at the W L{sub 3} (2p{sub 3/2}) edge, and compared the results with the refined crystal structure. XAS studies of anion binding are feasible even if only weak interactions are present, are biologically relevant, and give new insights in the spectroscopy.

  13. Anion binding in biological systems

    International Nuclear Information System (INIS)

    Feiters, Martin C; Meyer-Klaucke, Wolfram; Kostenko, Alexander V; Soldatov, Alexander V; Leblanc, Catherine; Michel, Gurvan; Potin, Philippe; Kuepper, Frithjof C; Hollenstein, Kaspar; Locher, Kaspar P; Bevers, Loes E; Hagedoorn, Peter-Leon; Hagen, Wilfred R

    2009-01-01

    We compare aspects of biological X-ray absorption spectroscopy (XAS) studies of cations and anions, and report on some examples of anion binding in biological systems. Brown algae such as Laminaria digitata (oarweed) are effective accumulators of I from seawater, with tissue concentrations exceeding 50 mM, and the vanadate-containing enzyme haloperoxidase is implicated in halide accumulation. We have studied the chemical state of iodine and its biological role in Laminaria at the I K edge, and bromoperoxidase from Ascophyllum nodosum (knotted wrack) at the Br K edge. Mo is essential for many forms of life; W only for certain archaea, such as Archaeoglobus fulgidus and the hyperthermophilic archaeon Pyrococcus furiosus, and some bacteria. The metals are bound and transported as their oxo-anions, molybdate and tungstate, which are similar in size. The transport protein WtpA from P. furiosus binds tungstate more strongly than molybdate, and is related in sequence to Archaeoglobus fulgidus ModA, of which a crystal structure is known. We have measured A. fulgidus ModA with tungstate at the W L 3 (2p 3/2 ) edge, and compared the results with the refined crystal structure. XAS studies of anion binding are feasible even if only weak interactions are present, are biologically relevant, and give new insights in the spectroscopy.

  14. Anion binding in biological systems

    Science.gov (United States)

    Feiters, Martin C.; Meyer-Klaucke, Wolfram; Kostenko, Alexander V.; Soldatov, Alexander V.; Leblanc, Catherine; Michel, Gurvan; Potin, Philippe; Küpper, Frithjof C.; Hollenstein, Kaspar; Locher, Kaspar P.; Bevers, Loes E.; Hagedoorn, Peter-Leon; Hagen, Wilfred R.

    2009-11-01

    We compare aspects of biological X-ray absorption spectroscopy (XAS) studies of cations and anions, and report on some examples of anion binding in biological systems. Brown algae such as Laminaria digitata (oarweed) are effective accumulators of I from seawater, with tissue concentrations exceeding 50 mM, and the vanadate-containing enzyme haloperoxidase is implicated in halide accumulation. We have studied the chemical state of iodine and its biological role in Laminaria at the I K edge, and bromoperoxidase from Ascophyllum nodosum (knotted wrack) at the Br K edge. Mo is essential for many forms of life; W only for certain archaea, such as Archaeoglobus fulgidus and the hyperthermophilic archaeon Pyrococcus furiosus, and some bacteria. The metals are bound and transported as their oxo-anions, molybdate and tungstate, which are similar in size. The transport protein WtpA from P. furiosus binds tungstate more strongly than molybdate, and is related in sequence to Archaeoglobus fulgidus ModA, of which a crystal structure is known. We have measured A. fulgidus ModA with tungstate at the W L3 (2p3/2) edge, and compared the results with the refined crystal structure. XAS studies of anion binding are feasible even if only weak interactions are present, are biologically relevant, and give new insights in the spectroscopy.

  15. Culturally Relevant Cyberbullying Prevention

    OpenAIRE

    Phillips, Gregory John

    2017-01-01

    In this action research study, I, along with a student intervention committee of 14 members, developed a cyberbullying intervention for a large urban high school on the west coast. This high school contained a predominantly African American student population. I aimed to discover culturally relevant cyberbullying prevention strategies for African American students. The intervention committee selected video safety messages featuring African American actors as the most culturally relevant cyber...

  16. S-Nitrosothiol measurements in biological systems⋄

    Science.gov (United States)

    Gow, Andrew; Doctor, Allan; Mannick, Joan; Gaston, Benjamin

    2007-01-01

    S-Nitrosothiol (SNO) cysteine modifications are regulated signaling reactions that dramatically affect, and are affected by, protein conformation. The lability of the S-NO bond can make SNO-modified proteins cumbersome to measure accurately. Here, we review methodologies for detecting SNO modifications in biology. There are three caveats. 1) Many assays for biological SNOs are used near the limit of detection: standard curves must be in the biologically relevant concentration range. 2) The assays that are most reliable are those that modify SNO protein or peptide chemistry the least. 3) Each result should be quantitatively validated using more than one assay. Improved assays are needed and are in development. PMID:17379583

  17. The association of 83 plasma proteins with CHD mortality, BMI, HDL-, and total-cholesterol in men: applying multivariate statistics to identify proteins with prognostic value and biological relevance.

    Science.gov (United States)

    Heidema, A Geert; Thissen, Uwe; Boer, Jolanda M A; Bouwman, Freek G; Feskens, Edith J M; Mariman, Edwin C M

    2009-06-01

    In this study, we applied the multivariate statistical tool Partial Least Squares (PLS) to analyze the relative importance of 83 plasma proteins in relation to coronary heart disease (CHD) mortality and the intermediate end points body mass index, HDL-cholesterol and total cholesterol. From a Dutch monitoring project for cardiovascular disease risk factors, men who died of CHD between initial participation (1987-1991) and end of follow-up (January 1, 2000) (N = 44) and matched controls (N = 44) were selected. Baseline plasma concentrations of proteins were measured by a multiplex immunoassay. With the use of PLS, we identified 15 proteins with prognostic value for CHD mortality and sets of proteins associated with the intermediate end points. Subsequently, sets of proteins and intermediate end points were analyzed together by Principal Components Analysis, indicating that proteins involved in inflammation explained most of the variance, followed by proteins involved in metabolism and proteins associated with total-C. This study is one of the first in which the association of a large number of plasma proteins with CHD mortality and intermediate end points is investigated by applying multivariate statistics, providing insight in the relationships among proteins, intermediate end points and CHD mortality, and a set of proteins with prognostic value.

  18. The Limits to Relevance

    Science.gov (United States)

    Averill, M.; Briggle, A.

    2006-12-01

    Science policy and knowledge production lately have taken a pragmatic turn. Funding agencies increasingly are requiring scientists to explain the relevance of their work to society. This stems in part from mounting critiques of the "linear model" of knowledge production in which scientists operating according to their own interests or disciplinary standards are presumed to automatically produce knowledge that is of relevance outside of their narrow communities. Many contend that funded scientific research should be linked more directly to societal goals, which implies a shift in the kind of research that will be funded. While both authors support the concept of useful science, we question the exact meaning of "relevance" and the wisdom of allowing it to control research agendas. We hope to contribute to the conversation by thinking more critically about the meaning and limits of the term "relevance" and the trade-offs implicit in a narrow utilitarian approach. The paper will consider which interests tend to be privileged by an emphasis on relevance and address issues such as whose goals ought to be pursued and why, and who gets to decide. We will consider how relevance, narrowly construed, may actually limit the ultimate utility of scientific research. The paper also will reflect on the worthiness of research goals themselves and their relationship to a broader view of what it means to be human and to live in society. Just as there is more to being human than the pragmatic demands of daily life, there is more at issue with knowledge production than finding the most efficient ways to satisfy consumer preferences or fix near-term policy problems. We will conclude by calling for a balanced approach to funding research that addresses society's most pressing needs but also supports innovative research with less immediately apparent application.

  19. Relevant Subspace Clustering

    DEFF Research Database (Denmark)

    Müller, Emmanuel; Assent, Ira; Günnemann, Stephan

    2009-01-01

    Subspace clustering aims at detecting clusters in any subspace projection of a high dimensional space. As the number of possible subspace projections is exponential in the number of dimensions, the result is often tremendously large. Recent approaches fail to reduce results to relevant subspace...... clusters. Their results are typically highly redundant, i.e. many clusters are detected multiple times in several projections. In this work, we propose a novel model for relevant subspace clustering (RESCU). We present a global optimization which detects the most interesting non-redundant subspace clusters...... achieves top clustering quality while competing approaches show greatly varying performance....

  20. Biological radioprotector

    International Nuclear Information System (INIS)

    Stefanescu, Ioan; Titescu, Gheorghe; Tamaian, Radu; Haulica, Ion; Bild, Walther

    2002-01-01

    According to the patent description, the biological radioprotector is deuterium depleted water, DDW, produced by vacuum distillation with an isotopic content lower than natural value. It appears as such or in a mixture with natural water and carbon dioxide. It can be used for preventing and reducing the ionizing radiation effects upon humans or animal organisms, exposed therapeutically, professionally or accidentally to radiation. The most significant advantage of using DDW as biological radioprotector results from its way of administration. Indeed no one of the radioprotectors currently used today can be orally administrated, what reduces the patients' compliance to prophylactic administrations. The biological radioprotector is an unnoxious product obtained from natural water, which can be administrated as food additive instead of drinking water. Dose modification factor is according to initial estimates around 1.9, what is a remarkable feature when one takes into account that the product is toxicity-free and side effect-free and can be administrated prophylactically as a food additive. A net radioprotective action of the deuterium depletion was evidenced experimentally in laboratory animals (rats) hydrated with DDW of 30 ppm D/(D+H) concentration as compared with normally hydrated control animals. Knowing the effects of irradiation and mechanisms of the acute radiation disease as well as the effects of administration of radiomimetic chemicals upon cellular lines of fast cell division, it appears that the effects of administrating DDW result from stimulation of the immunity system. In conclusion, the biological radioprotector DDW presents the following advantages: - it is obtained from natural products without toxicity; - it is easy to be administrated as a food additive, replacing the drinking water; - besides radioprotective effects, the product has also immunostimulative and antitumoral effects

  1. MAK- and BAT values list 2003. Maximum permissible concentrations at the place of work and biological tolerance values for working materials; MAK- und BAT-Werte-Liste 2003. Maximale Arbeitsplatzkonzentrationen und Biologische Arbeitsstofftoleranzwerte

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    The importance, application and derivation of the maximum concentrations at the workplace is explained. A material's list contains the presently valid maximum concentration values supplemented by a list of materials for which no such values were determined as yet. Furthermore there is a list of working materials clearly identified as carcinogenic, and of working materials with a sensitizing effect, aerosols and some specific working materials are discussed. Finally, the importance and the application of biological tolerance values is explained, supplemented by a materials list. (orig.) [German] In der vorliegenden neuesten Ausgabe werden erneut Bedeutung, Benutzung und Ableitung der MAK-Werte (maximale Arbeitsplatzkonzentrationen) erlaeutert. Eine Stoffliste enthaelt die derzeit gueltigen MAK-Werte, ergaenzt durch eine Aufzaehlung von Stoffen, fuer die noch keine MAK-Werte aufgestellt werden koennen. Es folgt eine Auflistung der Arbeitsstoffe, die bereits eindeutig als krebserregend ausgewiesen wurden, sowie der sensibilisierenden Arbeitsstoffe, Aerosole und einige besondere Arbeitsstoffe. Abschliessend wird die Bedeutung und Benutzung der BAT-Werte erlaeutert, ergaenzt durch eine Stoffliste. (orig.)

  2. Is Information Still Relevant?

    Science.gov (United States)

    Ma, Lia

    2013-01-01

    Introduction: The term "information" in information science does not share the characteristics of those of a nomenclature: it does not bear a generally accepted definition and it does not serve as the bases and assumptions for research studies. As the data deluge has arrived, is the concept of information still relevant for information…

  3. Fluid mechanics relevant to flow through pretreatment of cellulosic biomass.

    Science.gov (United States)

    Archambault-Léger, Véronique; Lynd, Lee R

    2014-04-01

    The present study investigates fluid mechanical properties of cellulosic feedstocks relevant to flow through (FT) pretreatment for biological conversion of cellulosic biomass. The results inform identifying conditions for which FT pretreatment can be implemented in a practical context. Measurements of pressure drop across packed beds, viscous compaction and water absorption are reported for milled and not milled sugarcane bagasse, switchgrass and poplar, and important factors impacting viscous flow are deduced. Using biomass knife-milled to pass through a 2mm sieve, the observed pressure drop was highest for bagasse, intermediate for switchgrass and lowest for poplar. The highest pressure drop was associated with the presence of more fine particles, greater viscous compaction and the degree of water absorption. Using bagasse without particle size reduction, the instability of the reactor during pretreatment above 140kg/m(3) sets an upper bound on the allowable concentration for continuous stable flow. Copyright © 2014. Published by Elsevier Ltd.

  4. Clinical Relevance of Adipokines

    Directory of Open Access Journals (Sweden)

    Matthias Blüher

    2012-10-01

    Full Text Available The incidence of obesity has increased dramatically during recent decades. Obesity increases the risk for metabolic and cardiovascular diseases and may therefore contribute to premature death. With increasing fat mass, secretion of adipose tissue derived bioactive molecules (adipokines changes towards a pro-inflammatory, diabetogenic and atherogenic pattern. Adipokines are involved in the regulation of appetite and satiety, energy expenditure, activity, endothelial function, hemostasis, blood pressure, insulin sensitivity, energy metabolism in insulin sensitive tissues, adipogenesis, fat distribution and insulin secretion in pancreatic β-cells. Therefore, adipokines are clinically relevant as biomarkers for fat distribution, adipose tissue function, liver fat content, insulin sensitivity, chronic inflammation and have the potential for future pharmacological treatment strategies for obesity and its related diseases. This review focuses on the clinical relevance of selected adipokines as markers or predictors of obesity related diseases and as potential therapeutic tools or targets in metabolic and cardiovascular diseases.

  5. Biological efficiency of Agaricus brasiliensis cultivated in compost with nitrogen concentrations Eficiência biológica de Agaricus brasiliensis em composto com concentrações de nitrogênio

    Directory of Open Access Journals (Sweden)

    Félix G de Siqueira

    2011-06-01

    Full Text Available The production of compost is one of the most important steps for the cultivation of any species of mushroom. For the Agaricus species, this step is even more complex because it depends on the performance of different microorganisms that act on the substrate, turning it into selective compost that promotes the growth of the fungus to be cultivated. Among the various factors that affect the microbial activity, the initial concentration of nitrogen is considered one of the most important. Due to the lack of conclusive studies about that, the aim of this study was to evaluate the productivity and biological efficiency of Agaricus brasiliensis in compost prepared with different initial concentrations of nitrogen, according to the composting methodology and to the conventional pasteurization techniques (phase I and II. Three initial nitrogen concentrations (w/w (T1= 1.0%; T2= 1.5%; and T3= 2.0% were tested and mycelial growth was determined in terms of mm/day for all treatments. The productivity and biological efficiency were also determined. The most efficient initial concentrations of nitrogen were of 1.0% and 1.5%. This concentration of N in the compost permitted a faster development of the mushroom with higher productivity when compared to the results obtained with the application of 2% of nitrogen.A produção do composto é uma das etapas mais importantes para o cultivo de qualquer espécie de cogumelo. Para as espécies Agaricus, essa etapa é ainda mais complexa, porque depende da atuação de diferentes microrganismos que atuam sobre o substrato, transformando-o em um composto seletivo que favorece o crescimento do fungo a ser cultivado. Dentre os diversos fatores que afetam essa atividade microbiana, a concentração inicial de nitrogênio é considerada uma das mais importantes. Em função da falta de estudos conclusivos a respeito, este trabalho teve por objetivo avaliar a produtividade e eficiência biológica de Agaricus brasiliensis em

  6. Information Needs/Relevance

    OpenAIRE

    Wildemuth, Barbara M.

    2009-01-01

    A user's interaction with a DL is often initiated as the result of the user experiencing an information need of some kind. Aspects of that experience and how it might affect the user's interactions with the DL are discussed in this module. In addition, users continuously make decisions about and evaluations of the materials retrieved from a DL, relative to their information needs. Relevance judgments, and their relationship to the user's information needs, are discussed in this module. Draft

  7. Biological Agents

    Science.gov (United States)

    ... E-Tools Safety and Health Topics / Biological Agents Biological Agents This page requires that javascript be enabled ... 202) 693-2300 if additional assistance is required. Biological Agents Menu Overview In Focus: Ebola Frederick A. ...

  8. Fast x-ray fluorescence microtomography of hydrated biological samples.

    Directory of Open Access Journals (Sweden)

    Enzo Lombi

    Full Text Available Metals and metalloids play a key role in plant and other biological systems as some of them are essential to living organisms and all can be toxic at high concentrations. It is therefore important to understand how they are accumulated, complexed and transported within plants. In situ imaging of metal distribution at physiological relevant concentrations in highly hydrated biological systems is technically challenging. In the case of roots, this is mainly due to the possibility of artifacts arising during sample preparation such as cross sectioning. Synchrotron x-ray fluorescence microtomography has been used to obtain virtual cross sections of elemental distributions. However, traditionally this technique requires long data acquisition times. This has prohibited its application to highly hydrated biological samples which suffer both radiation damage and dehydration during extended analysis. However, recent advances in fast detectors coupled with powerful data acquisition approaches and suitable sample preparation methods can circumvent this problem. We demonstrate the heightened potential of this technique by imaging the distribution of nickel and zinc in hydrated plant roots. Although 3D tomography was still impeded by radiation damage, we successfully collected 2D tomograms of hydrated plant roots exposed to environmentally relevant metal concentrations for short periods of time. To our knowledge, this is the first published example of the possibilities offered by a new generation of fast fluorescence detectors to investigate metal and metalloid distribution in radiation-sensitive, biological samples.

  9. The Biology of Cancer Health Disparities

    Science.gov (United States)

    These examples show how biology contributes to health disparities (differences in disease incidence and outcomes among distinct racial and ethnic groups, ), and how biological factors interact with other relevant factors, such as diet and the environment.

  10. Spatial Modeling Tools for Cell Biology

    National Research Council Canada - National Science Library

    Przekwas, Andrzej; Friend, Tom; Teixeira, Rodrigo; Chen, Z. J; Wilkerson, Patrick

    2006-01-01

    .... Scientific potentials and military relevance of computational biology and bioinformatics have inspired DARPA/IPTO's visionary BioSPICE project to develop computational framework and modeling tools for cell biology...

  11. Concentrated Ownership

    DEFF Research Database (Denmark)

    Rose, Caspar

    2014-01-01

    This entry summarizes the main theoretical contributions and empirical findings in relation to concentrated ownership from a law and economics perspective. The various forms of concentrated ownership are described as well as analyzed from the perspective of the legal protection of investors......, especially minority shareholders. Concentrated ownership is associated with benefits and costs. Concentrated ownership may reduce agency costs by increased monitoring of top management. However, concentrated ownership may also provide dominating owners with private benefits of control....

  12. Tailor-Made Fluorescent Trilobolide To Study Its Biological Relevance

    Czech Academy of Sciences Publication Activity Database

    Jurášek, M.; Rimpelová, S.; Kmoníčková, Eva; Drašar, P.; Ruml, T.

    2014-01-01

    Roč. 57, č. 19 (2014), s. 7947-7954 ISSN 0022-2623 Grant - others:GA ČR(CZ) GA14-28334S; GA MŠMT(CZ) 20/2014 Program:GA Institutional support: RVO:68378041 Keywords : trilobolide * nitric oxide * endoplasmic reticulum Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 5.447, year: 2014

  13. Towards a barrier height benchmark set for biologically relevant systems.

    Science.gov (United States)

    Kromann, Jimmy C; Christensen, Anders S; Cui, Qiang; Jensen, Jan H

    2016-01-01

    We have collected computed barrier heights and reaction energies (and associated model structures) for five enzymes from studies published by Himo and co-workers. Using this data, obtained at the B3LYP/6- 311+G(2d,2p)[LANL2DZ]//B3LYP/6-31G(d,p) level of theory, we then benchmark PM6, PM7, PM7-TS, and DFTB3 and discuss the influence of system size, bulk solvation, and geometry re-optimization on the error. The mean absolute differences (MADs) observed for these five enzyme model systems are similar to those observed for PM6 and PM7 for smaller systems (10-15 kcal/mol), while DFTB results in a MAD that is significantly lower (6 kcal/mol). The MADs for PMx and DFTB3 are each dominated by large errors for a single system and if the system is disregarded the MADs fall to 4-5 kcal/mol. Overall, results for the condensed phase are neither more or less accurate relative to B3LYP than those in the gas phase. With the exception of PM7-TS, the MAD for small and large structural models are very similar, with a maximum deviation of 3 kcal/mol for PM6. Geometry optimization with PM6 shows that for one system this method predicts a different mechanism compared to B3LYP/6-31G(d,p). For the remaining systems, geometry optimization of the large structural model increases the MAD relative to single points, by 2.5 and 1.8 kcal/mol for barriers and reaction energies. For the small structural model, the corresponding MADs decrease by 0.4 and 1.2 kcal/mol, respectively. However, despite these small changes, significant changes in the structures are observed for some systems, such as proton transfer and hydrogen bonding rearrangements. The paper represents the first step in the process of creating a benchmark set of barriers computed for systems that are relatively large and representative of enzymatic reactions, a considerable challenge for any one research group but possible through a concerted effort by the community. We end by outlining steps needed to expand and improve the data set and how other researchers can contribute to the process.

  14. Towards a barrier height benchmark set for biologically relevant systems

    Directory of Open Access Journals (Sweden)

    Jimmy C. Kromann

    2016-05-01

    Full Text Available We have collected computed barrier heights and reaction energies (and associated model structures for five enzymes from studies published by Himo and co-workers. Using this data, obtained at the B3LYP/6- 311+G(2d,2p[LANL2DZ]//B3LYP/6-31G(d,p level of theory, we then benchmark PM6, PM7, PM7-TS, and DFTB3 and discuss the influence of system size, bulk solvation, and geometry re-optimization on the error. The mean absolute differences (MADs observed for these five enzyme model systems are similar to those observed for PM6 and PM7 for smaller systems (10–15 kcal/mol, while DFTB results in a MAD that is significantly lower (6 kcal/mol. The MADs for PMx and DFTB3 are each dominated by large errors for a single system and if the system is disregarded the MADs fall to 4–5 kcal/mol. Overall, results for the condensed phase are neither more or less accurate relative to B3LYP than those in the gas phase. With the exception of PM7-TS, the MAD for small and large structural models are very similar, with a maximum deviation of 3 kcal/mol for PM6. Geometry optimization with PM6 shows that for one system this method predicts a different mechanism compared to B3LYP/6-31G(d,p. For the remaining systems, geometry optimization of the large structural model increases the MAD relative to single points, by 2.5 and 1.8 kcal/mol for barriers and reaction energies. For the small structural model, the corresponding MADs decrease by 0.4 and 1.2 kcal/mol, respectively. However, despite these small changes, significant changes in the structures are observed for some systems, such as proton transfer and hydrogen bonding rearrangements. The paper represents the first step in the process of creating a benchmark set of barriers computed for systems that are relatively large and representative of enzymatic reactions, a considerable challenge for any one research group but possible through a concerted effort by the community. We end by outlining steps needed to expand and improve the data set and how other researchers can contribute to the process.

  15. Single Molecule Fluorescence: from Physical Fascination to Biological Relevance

    NARCIS (Netherlands)

    Segers-Nolten, Gezina M.J.

    2003-01-01

    Confocal fluorescence microscopy is particularly well-known from the beautiful images that have been obtained with this technique from cells. Several cellular components could be nicely visualized simultaneously by staining them with different fluorophores. Not only for ensemble applications but

  16. Epigenetics in prostate cancer: biologic and clinical relevance.

    Science.gov (United States)

    Jerónimo, Carmen; Bastian, Patrick J; Bjartell, Anders; Carbone, Giuseppina M; Catto, James W F; Clark, Susan J; Henrique, Rui; Nelson, William G; Shariat, Shahrokh F

    2011-10-01

    Prostate cancer (PCa) is one of the most common human malignancies and arises through genetic and epigenetic alterations. Epigenetic modifications include DNA methylation, histone modifications, and microRNAs (miRNA) and produce heritable changes in gene expression without altering the DNA coding sequence. To review progress in the understanding of PCa epigenetics and to focus upon translational applications of this knowledge. PubMed was searched for publications regarding PCa and DNA methylation, histone modifications, and miRNAs. Reports were selected based on the detail of analysis, mechanistic support of data, novelty, and potential clinical applications. Aberrant DNA methylation (hypo- and hypermethylation) is the best-characterized alteration in PCa and leads to genomic instability and inappropriate gene expression. Global and locus-specific changes in chromatin remodeling are implicated in PCa, with evidence suggesting a causative dysfunction of histone-modifying enzymes. MicroRNA deregulation also contributes to prostate carcinogenesis, including interference with androgen receptor signaling and apoptosis. There are important connections between common genetic alterations (eg, E twenty-six fusion genes) and the altered epigenetic landscape. Owing to the ubiquitous nature of epigenetic alterations, they provide potential biomarkers for PCa detection, diagnosis, assessment of prognosis, and post-treatment surveillance. Altered epigenetic gene regulation is involved in the genesis and progression of PCa. Epigenetic alterations may provide valuable tools for the management of PCa patients and be targeted by pharmacologic compounds that reverse their nature. The potential for epigenetic changes in PCa requires further exploration and validation to enable translation to the clinic. Copyright © 2011 European Association of Urology. Published by Elsevier B.V. All rights reserved.

  17. Relevant Features of Science: Values in Conservation Biology

    Science.gov (United States)

    van Dijk, Esther M.

    2013-01-01

    The development of an understanding of the nature of science is generally assumed to be an important aspect of science communication with respect to the enhancement of scientific literacy. At present, a general characterization of the nature of science is still lacking and probably such a characterization will not be achievable. The overall aim of…

  18. [Relevant public health enteropathogens].

    Science.gov (United States)

    Riveros, Maribel; Ochoa, Theresa J

    2015-01-01

    Diarrhea remains the third leading cause of death in children under five years, despite recent advances in the management and prevention of this disease. It is caused by multiple pathogens, however, the prevalence of each varies by age group, geographical area and the scenario where cases (community vs hospital) are recorded. The most relevant pathogens in public health are those associated with the highest burden of disease, severity, complications and mortality. In our country, norovirus, Campylobacter and diarrheagenic E. coli are the most prevalent pathogens at the community level in children. In this paper we review the local epidemiology and potential areas of development in five selected pathogens: rotavirus, norovirus, Shiga toxin-producing E. coli (STEC), Shigella and Salmonella. Of these, rotavirus is the most important in the pediatric population and the main agent responsible for child mortality from diarrhea. The introduction of rotavirus vaccination in Peru will have a significant impact on disease burden and mortality from diarrhea. However, surveillance studies are needed to determine the impact of vaccination and changes in the epidemiology of diarrhea in Peru following the introduction of new vaccines, as well as antibiotic resistance surveillance of clinical relevant bacteria.

  19. Hyperpolarized NMR Probes for Biological Assays

    Directory of Open Access Journals (Sweden)

    Sebastian Meier

    2014-01-01

    Full Text Available During the last decade, the development of nuclear spin polarization enhanced (hyperpolarized molecular probes has opened up new opportunities for studying the inner workings of living cells in real time. The hyperpolarized probes are produced ex situ, introduced into biological systems and detected with high sensitivity and contrast against background signals using high resolution NMR spectroscopy. A variety of natural, derivatized and designed hyperpolarized probes has emerged for diverse biological studies including assays of intracellular reaction progression, pathway kinetics, probe uptake and export, pH, redox state, reactive oxygen species, ion concentrations, drug efficacy or oncogenic signaling. These probes are readily used directly under natural conditions in biofluids and are often directly developed and optimized for cellular assays, thus leaving little doubt about their specificity and utility under biologically relevant conditions. Hyperpolarized molecular probes for biological NMR spectroscopy enable the unbiased detection of complex processes by virtue of the high spectral resolution, structural specificity and quantifiability of NMR signals. Here, we provide a survey of strategies used for the selection, design and use of hyperpolarized NMR probes in biological assays, and describe current limitations and developments.

  20. Elliptical concentrators.

    Science.gov (United States)

    Garcia-Botella, Angel; Fernandez-Balbuena, Antonio Alvarez; Bernabeu, Eusebio

    2006-10-10

    Nonimaging optics is a field devoted to the design of optical components for applications such as solar concentration or illumination. In this field, many different techniques have been used to produce optical devices, including the use of reflective and refractive components or inverse engineering techniques. However, many of these optical components are based on translational symmetries, rotational symmetries, or free-form surfaces. We study a new family of nonimaging concentrators called elliptical concentrators. This new family of concentrators provides new capabilities and can have different configurations, either homofocal or nonhomofocal. Translational and rotational concentrators can be considered as particular cases of elliptical concentrators.

  1. Vygotsky's Crisis: Argument, context, relevance.

    Science.gov (United States)

    Hyman, Ludmila

    2012-06-01

    Vygotsky's The Historical Significance of the Crisis in Psychology (1926-1927) is an important text in the history and philosophy of psychology that has only become available to scholars in 1982 in Russian, and in 1997 in English. The goal of this paper is to introduce Vygotsky's conception of psychology to a wider audience. I argue that Vygotsky's argument about the "crisis" in psychology and its resolution can be fully understood only in the context of his social and political thinking. Vygotsky shared the enthusiasm, widespread among Russian leftist intelligentsia in the 1920s, that Soviet society had launched an unprecedented social experiment: The socialist revolution opened the way for establishing social conditions that would let the individual flourish. For Vygotsky, this meant that "a new man" of the future would become "the first and only species in biology that would create itself." He envisioned psychology as a science that would serve this humanist teleology. I propose that The Crisis is relevant today insofar as it helps us define a fundamental problem: How can we systematically account for the development of knowledge in psychology? I evaluate how Vygotsky addresses this problem as a historian of the crisis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Concentration risk

    Directory of Open Access Journals (Sweden)

    Matić Vesna

    2016-01-01

    Full Text Available Concentration risk has been gaining a special dimension in the contemporary financial and economic environment. Financial institutions are exposed to this risk mainly in the field of lending, mostly through their credit activities and concentration of credit portfolios. This refers to the concentration of different exposures within a single risk category (credit risk, market risk, operational risk, liquidity risk.

  3. Concentrator Photovoltaics

    CERN Document Server

    Luque, Antonio L

    2007-01-01

    Photovoltaic solar-energy conversion is one of the most promising technologies for generating renewable energy, and conversion of concentrated sunlight can lead to reduced cost for solar electricity. In fact, photovoltaic conversion of concentrated sunlight insures an efficient and cost-effective sustainable power resource. This book gives an overview of all components, e.g. cells, concentrators, modules and systems, for systems of concentrator photovoltaics. The authors report on significant results related to design, technology, and applications, and also cover the fundamental physics and market considerations. Specific contributions include: theory and practice of sunlight concentrators; an overview of concentrator PV activities; a description of concentrator solar cells; design and technology of modules and systems; manufacturing aspects; and a market study.

  4. User perspectives on relevance criteria

    DEFF Research Database (Denmark)

    Maglaughlin, Kelly L.; Sonnenwald, Diane H.

    2002-01-01

    , partially relevant, or not relevant to their information need; and explained their decisions in an interview. Analysis revealed 29 criteria, discussed positively and negatively, that were used by the participants when selecting passages that contributed or detracted from a document's relevance......This study investigates the use of criteria to assess relevant, partially relevant, and not-relevant documents. Study participants identified passages within 20 document representations that they used to make relevance judgments; judged each document representation as a whole to be relevant...... matter, thought catalyst), full text (e.g., audience, novelty, type, possible content, utility), journal/publisher (e.g., novelty, main focus, perceived quality), and personal (e.g., competition, time requirements). Results further indicate that multiple criteria are used when making relevant, partially...

  5. Modern Biology

    OpenAIRE

    ALEKSIC, Branko

    2014-01-01

    The purpose of this course is to learn the philosophy, principles, and techniques of modern biology. The course is particularly designed for those who have not learned biology previously or whose major is other than biology, and who may think that they do not need to know any biology at all. The topics are covered in a rather general, overview manner, but certain level of diligence in grasping concepts and memorizing the terminology is expected.

  6. Monochloramine Cometabolism by Nitrifying Biofilm Relevant ...

    Science.gov (United States)

    Recently, biological monochloramine removal (i.e., cometabolism) by a pure culture ammonia–oxidizing bacteria, Nitrosomonas europaea, and a nitrifying mixed–culture have been shown to increase monochloramine demand. Although important, these previous suspended culture batch kinetic experiments were not representative of drinking water distribution systems where bacteria grow predominantly as biofilm attached to pipe walls or sediments and physiological differences may exist between suspension and biofilm growth. Therefore, the current research was an important next step in extending the previous results to investigate monochloramine cometabolism by biofilm grown in annular reactors under drinking water relevant conditions. Estimated monochloramine cometabolism kinetics were similar to those of ammonia metabolism, and monochloramine cometabolism was a significant loss mechanism (25–40% of the observed monochloramine loss). These results demonstrated that monochloramine cometabolism occurred in drinking water relevant nitrifying biofilm; thus, cometabolism may be a significant contribution to monochloramine loss during nitrification episodes in distribution systems. Investigate whether or not nitrifying biofilm can biologically transform monochloramine under drinking water relevant conditions.

  7. Biological radiolesions and repair

    International Nuclear Information System (INIS)

    Laskowski, W.

    1981-01-01

    In 7 chapters, the book answers the following questions: 1) What reactions are induced in biological matter by absorption of radiation energy. 2) In what parts of the cell do the radiation-induced reactions with detectable biological effects occur. 3) In which way are these cell components changed by different qualities of radiation. 4) What are the cell mechanisms by which radiation-induced changes can be repaired. 5) What is the importance of these repair processes for man, his life and evolution. At the end of each chapter, there is a bibliography of relevant publications in this field. (orig./MG) [de

  8. Mathematical biology

    CERN Document Server

    Murray, James D

    1993-01-01

    The book is a textbook (with many exercises) giving an in-depth account of the practical use of mathematical modelling in the biomedical sciences. The mathematical level required is generally not high and the emphasis is on what is required to solve the real biological problem. The subject matter is drawn, e.g. from population biology, reaction kinetics, biological oscillators and switches, Belousov-Zhabotinskii reaction, reaction-diffusion theory, biological wave phenomena, central pattern generators, neural models, spread of epidemics, mechanochemical theory of biological pattern formation and importance in evolution. Most of the models are based on real biological problems and the predictions and explanations offered as a direct result of mathematical analysis of the models are important aspects of the book. The aim is to provide a thorough training in practical mathematical biology and to show how exciting and novel mathematical challenges arise from a genuine interdisciplinary involvement with the biosci...

  9. Bacteriophage lambda: early pioneer and still relevant

    Science.gov (United States)

    Casjens, Sherwood R.; Hendrix, Roger W.

    2015-01-01

    Molecular genetic research on bacteriophage lambda carried out during its golden age from the mid 1950's to mid 1980's was critically important in the attainment of our current understanding of the sophisticated and complex mechanisms by which the expression of genes is controlled, of DNA virus assembly and of the molecular nature of lysogeny. The development of molecular cloning techniques, ironically instigated largely by phage lambda researchers, allowed many phage workers to switch their efforts to other biological systems. Nonetheless, since that time the ongoing study of lambda and its relatives have continued to give important new insights. In this review we give some relevant early history and describe recent developments in understanding the molecular biology of lambda's life cycle. PMID:25742714

  10. Inferring relevance in a changing world

    Directory of Open Access Journals (Sweden)

    Robert C Wilson

    2012-01-01

    Full Text Available Reinforcement learning models of human and animal learning usually concentrate on how we learn the relationship between different stimuli or actions and rewards. However, in real world situations stimuli are ill-defined. On the one hand, our immediate environment is extremely multi-dimensional. On the other hand, in every decision-making scenario only a few aspects of the environment are relevant for obtaining reward, while most are irrelevant. Thus a key question is how do we learn these relevant dimensions, that is, how do we learn what to learn about? We investigated this process of representation learning experimentally, using a task in which one stimulus dimension was relevant for determining reward at each point in time. As in real life situations, in our task the relevant dimension can change without warning, adding ever-present uncertainty engendered by a constantly changing environment. We show that human performance on this task is better described by a suboptimal strategy based on selective attention and serial hypothesis testing rather than a normative strategy based on probabilistic inference. From this, we conjecture that the problem of inferring relevance in general scenarios is too computationally demanding for the brain to solve optimally. As a result the brain utilizes approximations, employing these even in simplified scenarios in which optimal representation learning is tractable, such as the one in our experiment.

  11. Concentrating Radioactivity

    Science.gov (United States)

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  12. On relevant boundary perturbations of unitary minimal models

    International Nuclear Information System (INIS)

    Recknagel, A.; Roggenkamp, D.; Schomerus, V.

    2000-01-01

    We consider unitary Virasoro minimal models on the disk with Cardy boundary conditions and discuss deformations by certain relevant boundary operators, analogous to tachyon condensation in string theory. Concentrating on the least relevant boundary field, we can perform a perturbative analysis of renormalization group fixed points. We find that the systems always flow towards stable fixed points which admit no further (non-trivial) relevant perturbations. The new conformal boundary conditions are in general given by superpositions of 'pure' Cardy boundary conditions

  13. Métodos de extração e/ou concentração de compostos encontrados em fluidos biológicos para posterior determinação cromatográfica Methods of extraction and/or concentration of compounds found in biological fluids for subsequent chromatographic determination

    Directory of Open Access Journals (Sweden)

    Sonia C. N. Queiroz

    2001-02-01

    Full Text Available When organic compounds present in biological fluids are analysed by chromatographic methods, it is generally necessary to carry out a prior sample preparation due the high complexity of this type of sample, especially when the compounds to be determinated are found in very low concentrations. This article describes some of the principal methods for sample preparation in analyses of substances present in biological fluids. The methods include liquid-liquid extraction, solid phase extraction, supercritical fluid extraction and extraction using solid and liquid membranes. The advantages and disadvantages of these methods are discussed.

  14. Biological therapeutics

    National Research Council Canada - National Science Library

    Greenstein, Ben; Brook, Daniel A

    2011-01-01

    This introductory textbook covers all the main categories of biological medicines, including vaccines, hormonal preparations, drugs for rheumatoid arthritis and other connective tissue diseases, drugs...

  15. Relevance in the science classroom: A multidimensional analysis

    Science.gov (United States)

    Hartwell, Matthew F.

    While perceived relevance is considered a fundamental component of adaptive learning, the experience of relevance and its conceptual definition have not been well described. The mixed-methods research presented in this dissertation aimed to clarify the conceptual meaning of relevance by focusing on its phenomenological experience from the students' perspective. Following a critical literature review, I propose an identity-based model of perceived relevance that includes three components: a contextual target, an identity target, and a connection type, or lens. An empirical investigation of this model that consisted of two general phases was implemented in four 9th grade-biology classrooms. Participants in Phase 1 (N = 118) completed a series of four open-ended writing activities focused on eliciting perceived personal connections to academic content. Exploratory qualitative content analysis of a 25% random sample of the student responses was used to identify the main meaning-units of the proposed model as well as different dimensions of student relevance perceptions. These meaning-units and dimensions provided the basis for the construction of a conceptual mapping sentence capturing students' perceived relevance, which was then applied in a confirmatory analysis to all other student responses. Participants in Phase 2 (N = 139) completed a closed survey designed based on the mapping sentence to assess their perceived relevance of a biology unit. The survey also included scales assessing other domain-level motivational processes. Exploratory factor analysis and non-metric multidimensional scaling indicated a coherent conceptual structure, which included a primary interpretive relevance dimension. Comparison of the conceptual structure across various groups (randomly-split sample, gender, academic level, domain-general motivational profiles) provided support for its ubiquity and insight into variation in the experience of perceived relevance among students of different

  16. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  17. Mesoscopic biology

    Indian Academy of Sciences (India)

    In this paper we present a qualitative outlook of mesoscopic biology where the typical length scale is of the order of nanometers and the energy scales comparable to thermal energy. Novel biomolecular machines, governed by coded information at the level of DNA and proteins, operate at these length scales in biological ...

  18. Quantum Biology

    Directory of Open Access Journals (Sweden)

    Alessandro Sergi

    2009-06-01

    Full Text Available A critical assessment of the recent developmentsof molecular biology is presented.The thesis that they do not lead to a conceptualunderstanding of life and biological systems is defended.Maturana and Varela's concept of autopoiesis is briefly sketchedand its logical circularity avoided by postulatingthe existence of underlying living processes,entailing amplification from the microscopic to the macroscopic scale,with increasing complexity in the passage from one scale to the other.Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces,is criticized. It is suggested that the correct interpretationof quantum dispersion forces (van der Waals, hydrogen bonding, and so onas quantum coherence effects hints at the necessity of includinglong-ranged forces (or mechanisms for them incondensed matter theories of biological processes.Some quantum effects in biology are reviewedand quantum mechanics is acknowledged as conceptually important to biology since withoutit most (if not all of the biological structuresand signalling processes would not even exist. Moreover, it is suggested that long-rangequantum coherent dynamics, including electron polarization,may be invoked to explain signal amplificationprocess in biological systems in general.

  19. Biological desulfurisation

    Energy Technology Data Exchange (ETDEWEB)

    Arena, B.J. [UOP LLC (United States); Benschop, A.; Janssen, A. [Paques Natural Solutions (Netherlands); Kijlstra, S. [Shell Global Solutions (Netherlands)

    2001-03-01

    This article focuses on the biological THIOPAQ process for removing hydrogen sulphide from refinery gases and recovering elemental sulphur. Details are given of the process which absorbs hydrogen sulphide-containing gas in alkaline solution prior to oxidation of the dissolved sulphur to elemental sulphur in a THIOPAQ aerobic biological reactor, with regeneration of the caustic solution. Sulphur handling options including sulphur wash, the drying of the sulphur cake, and sulphur smelting by pressure liquefaction are described. Agricultural applications of the biologically recovered sulphur, and application of the THIOPAQ process to sulphur recovery are discussed.

  20. Profiles of Dialogue for Relevance

    Directory of Open Access Journals (Sweden)

    Douglas Walton

    2016-12-01

    Full Text Available This paper uses argument diagrams, argumentation schemes, and some tools from formal argumentation systems developed in artificial intelligence to build a graph-theoretic model of relevance shown to be applicable (with some extensions as a practical method for helping a third party judge issues of relevance or irrelevance of an argument in real examples. Examples used to illustrate how the method works are drawn from disputes about relevance in natural language discourse, including a criminal trial and a parliamentary debate.

  1. [Cybernetics and biology].

    Science.gov (United States)

    Vasil'ev, G F

    2013-01-01

    Owing to methodical disadvantages, the theory of control still lacks the potential for the analysis of biological systems. To get the full benefit of the method in addition to the algorithmic model of control (as of today the only used model in the theory of control) a parametric model of control is offered to employ. The reasoning for it is explained. The approach suggested provides the possibility to use all potential of the modern theory of control for the analysis of biological systems. The cybernetic approach is shown taking a system of the rise of glucose concentration in blood as an example.

  2. Systems Biology

    Indian Academy of Sciences (India)

    IAS Admin

    study and understand the function of biological systems, particu- larly, the response of such .... understand the organisation and behaviour of prokaryotic sys- tems. ... relationship of the structure of a target molecule to its ability to bind a certain ...

  3. Spatial Structures and Regulation in Biological Systems

    DEFF Research Database (Denmark)

    Yde, Pernille

    , and the other is the spatial regulation of biological systems, here related to different aspects of the inflammatory response. All systems are studied using computational modelling and mathematical analysis. The first part of the thesis explores different protein aggregation scenarios. In Chapter 1, we consider...... a previously studied and very general aggregation model describing frangible linear filaments. This model is especially relevant for the growth of amyloid fibres, that have been related to a number of serious human diseases, and which are known to grow in an accelerated self-enhanced manner.We derive...... model of the tissue and show how coupled cells are able to function as an excitable medium and propagate waves of high cytokine concentration through the tissue. If the internal regulation in the cells is over-productive, the model predicts a continuous amplification of cytokines, which spans the entire...

  4. Biological phosphorus cycling in dryland regions

    Science.gov (United States)

    Belnap, Jayne; Bunemann, Else; Oberson, Astrid; Frossard, Emmanuel

    2011-01-01

    The relatively few studies done on phosphorus (P) cycling in arid and semiarid lands (drylands) show many factors that distinguish P cycling in drylands from that in more mesic regions. In drylands, most biologically relevant P inputs and losses are from the deposition and loss of dust. Horizontal and vertical redistribution of P is an important process. P is concentrated at the soil surface and thus vulnerable to loss via erosion. High pH and CaCO3 limit P bioavailability, and low rainfall limits microbe and plant ability to free abiotically bound P via exudates, thus making it available for uptake. Many invasive plants are able to access recalcitrant P more effectively than are native plants. As P availability depends on soil moisture and temperature, climate change is expected to have large impacts on P cycling

  5. A proposed abiotic reaction scheme for hydroxylamine and monochloramine under chloramination relevant drinking water conditions.

    Science.gov (United States)

    Wahman, David G; Speitel, Gerald E; Machavaram, Madhav V

    2014-09-01

    Drinking water monochloramine (NH2Cl) use may promote ammonia-oxidizing bacteria (AOB). AOB use (i) ammonia monooxygenase for biological ammonia (NH3) oxidation to hydroxylamine (NH2OH) and (ii) hydroxylamine oxidoreductase for NH2OH oxidation to nitrite. NH2Cl and NH2OH may react, providing AOB potential benefits and detriments. The NH2Cl/NH2OH reaction would benefit AOB by removing the disinfectant (NH2Cl) and releasing their growth substrate (NH3), but the NH2Cl/NH2OH reaction would also provide a possible additional inactivation mechanism besides direct NH2Cl reaction with cells. Because biological NH2OH oxidation supplies the electrons required for biological NH3 oxidation, the NH2Cl/NH2OH reaction provides a direct mechanism for NH2Cl to inhibit NH3 oxidation, starving the cell of reductant by preventing biological NH2OH oxidation. To investigate possible NH2Cl/NH2OH reaction implications on AOB, an understanding of the underlying abiotic reaction is first required. The present study conducted a detailed literature review and proposed an abiotic NH2Cl/NH2OH reaction scheme (RS) for chloramination relevant drinking water conditions (μM concentrations, air saturation, and pH 7-9). Next, RS literature based kinetics and end-products were evaluated experimentally between pHs 7.7 and 8.3, representing (i) the pH range for future experiments with AOB and (ii) mid-range pHs typically found in chloraminated drinking water. In addition, a (15)N stable isotope experiment was conducted to verify nitrous oxide and nitrogen gas production and their nitrogen source. Finally, the RS was slightly refined using the experimental data and an AQUASIM implemented kinetic model. A chloraminated drinking water relevant RS is proposed and provides the abiotic reaction foundation for future AOB biotic experiments. Published by Elsevier Ltd.

  6. Relevance theory: pragmatics and cognition.

    Science.gov (United States)

    Wearing, Catherine J

    2015-01-01

    Relevance Theory is a cognitively oriented theory of pragmatics, i.e., a theory of language use. It builds on the seminal work of H.P. Grice(1) to develop a pragmatic theory which is at once philosophically sensitive and empirically plausible (in both psychological and evolutionary terms). This entry reviews the central commitments and chief contributions of Relevance Theory, including its Gricean commitment to the centrality of intention-reading and inference in communication; the cognitively grounded notion of relevance which provides the mechanism for explaining pragmatic interpretation as an intention-driven, inferential process; and several key applications of the theory (lexical pragmatics, metaphor and irony, procedural meaning). Relevance Theory is an important contribution to our understanding of the pragmatics of communication. © 2014 John Wiley & Sons, Ltd.

  7. Clinical relevance in anesthesia journals

    DEFF Research Database (Denmark)

    Lauritsen, Jakob; Møller, Ann M

    2006-01-01

    The purpose of this review is to present the latest knowledge and research on the definition and distribution of clinically relevant articles in anesthesia journals. It will also discuss the importance of the chosen methodology and outcome of articles.......The purpose of this review is to present the latest knowledge and research on the definition and distribution of clinically relevant articles in anesthesia journals. It will also discuss the importance of the chosen methodology and outcome of articles....

  8. An Improved Optimization Method for the Relevance Voxel Machine

    DEFF Research Database (Denmark)

    Ganz, Melanie; Sabuncu, M. R.; Van Leemput, Koen

    2013-01-01

    In this paper, we will re-visit the Relevance Voxel Machine (RVoxM), a recently developed sparse Bayesian framework used for predicting biological markers, e.g., presence of disease, from high-dimensional image data, e.g., brain MRI volumes. The proposed improvement, called IRVoxM, mitigates the ...

  9. Long-time data storage: relevant time scales

    NARCIS (Netherlands)

    Elwenspoek, Michael Curt

    2011-01-01

    Dynamic processes relevant for long-time storage of information about human kind are discussed, ranging from biological and geological processes to the lifecycle of stars and the expansion of the universe. Major results are that life will end ultimately and the remaining time that the earth is

  10. Reflections on rural people's knowledge and skill and relevance in ...

    African Journals Online (AJOL)

    UNLICENSED

    objective is to assess the relevance of indigenous knowledge in agriculture. ... transmit the knowledge to the youths and researchers to document it and government to protect it. ... mechanisms to protect the earth's biological diversity. ... and other development agencies to embrace Agenda 21 as .... ecological characteristics.

  11. Stress and adaptation : Toward ecologically relevant animal models

    NARCIS (Netherlands)

    Koolhaas, Jaap M.; Boer, Sietse F. de; Buwalda, Bauke

    Animal models have contributed considerably to the current understanding of mechanisms underlying the role of stress in health and disease. Despite the progress made already, much more can be made by more carefully exploiting animals' and humans' shared biology, using ecologically relevant models.

  12. Mesoscopic models of biological membranes

    DEFF Research Database (Denmark)

    Venturoli, M.; Sperotto, Maria Maddalena; Kranenburg, M.

    2006-01-01

    Phospholipids are the main components of biological membranes and dissolved in water these molecules self-assemble into closed structures, of which bilayers are the most relevant from a biological point of view. Lipid bilayers are often used, both in experimental and by theoretical investigations...... to coarse grain a biological membrane. The conclusion of this comparison is that there can be many valid different strategies, but that the results obtained by the various mesoscopic models are surprisingly consistent. A second objective of this review is to illustrate how mesoscopic models can be used...

  13. Approaches to chemical synthetic biology.

    Science.gov (United States)

    Chiarabelli, Cristiano; Stano, Pasquale; Anella, Fabrizio; Carrara, Paolo; Luisi, Pier Luigi

    2012-07-16

    Synthetic biology is first represented in terms of two complementary aspects, the bio-engineering one, based on the genetic manipulation of extant microbial forms in order to obtain forms of life which do not exist in nature; and the chemical synthetic biology, an approach mostly based on chemical manipulation for the laboratory synthesis of biological structures that do not exist in nature. The paper is mostly devoted to shortly review chemical synthetic biology projects currently carried out in our laboratory. In particular, we describe: the minimal cell project, then the "Never Born Proteins" and lastly the Never Born RNAs. We describe and critically analyze the main results, emphasizing the possible relevance of chemical synthetic biology for the progress in basic science and biotechnology. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  14. Biological treatment of Crohn's disease

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Bjerrum, Jacob Tveiten; Seidelin, Jakob Benedict

    2012-01-01

    Introduction of biological agents for the treatment of Crohn's disease (CD) has led to a transformation of the treatment paradigm. Several biological compounds have been approved for patients with CD refractory to conventional treatment: infliximab, adalimumab and certolizumab pegol (and...... natalizumab in several countries outside the European Union). However, despite the use of biologics for more than a decade, questions still remain about the true efficacy and the best treatment regimens - especially about when to discontinue treatment. Furthermore, a need for optimizing treatment...... with biologics still exists, as 20-40% of patients with CD (depending on selection criteria) do not have any relevant response to the current biological agents (i.e. primary failures). A better patient selection might maximize the clinical outcome while minimizing the complications associated with this type...

  15. EURASIP journal on bioinformatics & systems biology

    National Research Council Canada - National Science Library

    2006-01-01

    "The overall aim of "EURASIP Journal on Bioinformatics and Systems Biology" is to publish research results related to signal processing and bioinformatics theories and techniques relevant to a wide...

  16. [Biological agents].

    Science.gov (United States)

    Amano, Koichi

    2009-03-01

    There are two types of biological agents for the treatment of rheumatoid arthritis (RA); monoclonal antibodies and recombinant proteins. Among the latter, etanercept, a recombinant fusion protein of soluble TNF receptor and IgG was approved in 2005 in Japan. The post-marketing surveillance of 13,894 RA patients revealed the efficacy and safety profiles of etanercept in the Japanese population, as well as overseas studies. Abatacept, a recombinant fusion protein of CTLA4 and IgG, is another biological agent for RA. Two clinical trials disclosed the efficacy of abatacept for difficult-to-treat patients: the AIM for MTX-resistant cases and the ATTAIN for patients who are resistant to anti-TNF. The ATTEST trial suggested abatacept might have more acceptable safety profile than infliximab. These biologics are also promising for the treatment of RA for not only relieving clinical symptoms and signs but retarding structural damage.

  17. Biological preconcentrator

    Science.gov (United States)

    Manginell, Ronald P [Albuquerque, NM; Bunker, Bruce C [Albuquerque, NM; Huber, Dale L [Albuquerque, NM

    2008-09-09

    A biological preconcentrator comprises a stimulus-responsive active film on a stimulus-producing microfabricated platform. The active film can comprise a thermally switchable polymer film that can be used to selectively absorb and desorb proteins from a protein mixture. The biological microfabricated platform can comprise a thin membrane suspended on a substrate with an integral resistive heater and/or thermoelectric cooler for thermal switching of the active polymer film disposed on the membrane. The active polymer film can comprise hydrogel-like polymers, such as poly(ethylene oxide) or poly(n-isopropylacrylamide), that are tethered to the membrane. The biological preconcentrator can be fabricated with semiconductor materials and technologies.

  18. Bayes in biological anthropology.

    Science.gov (United States)

    Konigsberg, Lyle W; Frankenberg, Susan R

    2013-12-01

    In this article, we both contend and illustrate that biological anthropologists, particularly in the Americas, often think like Bayesians but act like frequentists when it comes to analyzing a wide variety of data. In other words, while our research goals and perspectives are rooted in probabilistic thinking and rest on prior knowledge, we often proceed to use statistical hypothesis tests and confidence interval methods unrelated (or tenuously related) to the research questions of interest. We advocate for applying Bayesian analyses to a number of different bioanthropological questions, especially since many of the programming and computational challenges to doing so have been overcome in the past two decades. To facilitate such applications, this article explains Bayesian principles and concepts, and provides concrete examples of Bayesian computer simulations and statistics that address questions relevant to biological anthropology, focusing particularly on bioarchaeology and forensic anthropology. It also simultaneously reviews the use of Bayesian methods and inference within the discipline to date. This article is intended to act as primer to Bayesian methods and inference in biological anthropology, explaining the relationships of various methods to likelihoods or probabilities and to classical statistical models. Our contention is not that traditional frequentist statistics should be rejected outright, but that there are many situations where biological anthropology is better served by taking a Bayesian approach. To this end it is hoped that the examples provided in this article will assist researchers in choosing from among the broad array of statistical methods currently available. Copyright © 2013 Wiley Periodicals, Inc.

  19. Shippingport: A relevant decommissioning project

    International Nuclear Information System (INIS)

    Crimi, F.P.

    1988-01-01

    Because of Shippingport's low electrical power rating (72 MWe), there has been some misunderstanding on the relevancy of the Shippingport Station Decommissioning Project (SSDP) to a modern 1175 MWe commercial pressurized water reactor (PWR) power station. This paper provides a comparison of the major components of the reactor plant of the 72 MWe Shippingport Atomic Power Station and an 1175 MWe nuclear plant and the relevancy of the Shippingport decommissioning as a demonstration project for the nuclear industry. For the purpose of this comparison, Portland General Electric Company's 1175 MWe Trojan Nuclear Plant at Rainier, Oregon, has been used as the reference nuclear power plant. 2 refs., 2 figs., 1 tab

  20. Environmental biology

    International Nuclear Information System (INIS)

    Tschumi, P.A.

    1981-01-01

    Environmental biology illustrates the functioning of ecosystems and the dynamics of populations with many examples from limnology and terrestrial ecology. On this basis, present environmental problems are analyzed. The present environmental crisis is seen as a result of the failure to observe ecological laws. (orig.) [de

  1. Biological timekeeping

    DEFF Research Database (Denmark)

    Lloyd, David

    2016-01-01

    , the networks that connect differenttime domains and the oscillations, rhythms and biological clocks that coordinate andsynchronise the complexity of the living state.“It is the pattern maintained by this homeostasis, which is the touchstone ofour personal identity. Our tissues change as we live: the food we...

  2. Scaffolded biology.

    Science.gov (United States)

    Minelli, Alessandro

    2016-09-01

    Descriptions and interpretations of the natural world are dominated by dichotomies such as organism vs. environment, nature vs. nurture, genetic vs. epigenetic, but in the last couple of decades strong dissatisfaction with those partitions has been repeatedly voiced and a number of alternative perspectives have been suggested, from perspectives such as Dawkins' extended phenotype, Turner's extended organism, Oyama's Developmental Systems Theory and Odling-Smee's niche construction theory. Last in time is the description of biological phenomena in terms of hybrids between an organism (scaffolded system) and a living or non-living scaffold, forming unit systems to study processes such as reproduction and development. As scaffold, eventually, we can define any resource used by the biological system, especially in development and reproduction, without incorporating it as happens in the case of resources fueling metabolism. Addressing biological systems as functionally scaffolded systems may help pointing to functional relationships that can impart temporal marking to the developmental process and thus explain its irreversibility; revisiting the boundary between development and metabolism and also regeneration phenomena, by suggesting a conceptual framework within which to investigate phenomena of regular hypermorphic regeneration such as characteristic of deer antlers; fixing a periodization of development in terms of the times at which a scaffolding relationship begins or is terminated; and promoting plant galls to legitimate study objects of developmental biology.

  3. Biological digestion

    International Nuclear Information System (INIS)

    Rosevear, A.

    1988-01-01

    This paper discusses the biological degradation of non-radioactive organic material occurring in radioactive wastes. The biochemical steps are often performed using microbes or isolated enzymes in combination with chemical steps and the aim is to oxidise the carbon, hydrogen, nitrogen and sulphur to their respective oxides. (U.K.)

  4. Marine Biology

    Science.gov (United States)

    Dewees, Christopher M.; Hooper, Jon K.

    1976-01-01

    A variety of informational material for a course in marine biology or oceanology at the secondary level is presented. Among the topics discussed are: food webs and pyramids, planktonic blooms, marine life, plankton nets, food chains, phytoplankton, zooplankton, larval plankton and filter feeders. (BT)

  5. XAS Investigation of bio-relevant cobalt complexes in aqueous media

    International Nuclear Information System (INIS)

    Bresson, C.; Lamouroux, C.; Esnouf, S.; Solari, P.L.; Den Auwer, C.

    2006-01-01

    Cobalt is an essential element of biological cycles involved in numerous metallo-biomolecules, but it becomes a toxic element at high concentration or a radio-toxic element because of its use in the nuclear industry. 'Molecular speciation' in biological media is an essential prerequisite to evaluate its chemical behaviour as well as its toxic or beneficial effects. In this scheme, we have focused on the coordination properties of the thiol-containing amino acid cysteine (Cys) and the pseudo-peptide N-(2-mercapto-propionyl) glycine (MPG) towards the Co 2+ cation in aqueous media. XAS at the Co K edge and traditional spectroscopic techniques have been coupled in order to structurally characterize the cobalt coordination sphere. Oxidation states and geometries of the bis- and tris-cysteinato Co(III) complexes are in agreement with the literature data. In addition, bond lengths between the metallic centre and the donor atoms have been determined. The structure of a new dimeric N-(2-mercapto-propionyl) glycinato Co(II) complex in solution is also reported. The coordination of MPG to Co(II) through the thiolate and carboxylate functions is ascertained. This work provides fundamental structural information about bio-relevant complexes of cobalt, which will contribute to our understanding of the chemical behaviour and the biological role of this radionuclide. (authors)

  6. Dramatic lives and relevant becomings

    DEFF Research Database (Denmark)

    Henriksen, Ann-Karina; Miller, Jody

    2012-01-01

    of marginality into positions of relevance. The analysis builds on empirical data from Copenhagen, Denmark, gained through ethnographic fieldwork with the participation of 20 female informants aged 13–22. The theoretical contribution proposes viewing conflicts as multi-linear, multi-causal and non...

  7. Regularization in Matrix Relevance Learning

    NARCIS (Netherlands)

    Schneider, Petra; Bunte, Kerstin; Stiekema, Han; Hammer, Barbara; Villmann, Thomas; Biehl, Michael

    A In this paper, we present a regularization technique to extend recently proposed matrix learning schemes in learning vector quantization (LVQ). These learning algorithms extend the concept of adaptive distance measures in LVQ to the use of relevance matrices. In general, metric learning can

  8. Method of processing concentrated liquid waste in nuclear power plant

    International Nuclear Information System (INIS)

    Hasegawa, Kazuyuki; Kitsukawa, Ryozo; Ohashi, Satoru.

    1988-01-01

    Purpose: To reduce the oxidizable material in the concentrated liquid wastes discharged from nuclear power plants. Constitution: Nitrate bacteria are added to liquid wastes in a storage tank for temporarily storing concentrated liquid wastes or relevant facilities thereof. That is, nitrites as the oxidizable material contained in the concentrated liquid wastes are converted into nitrate non-deleterious to solidification by utilizing biological reaction of nitrate bacteria. For making the conversion more effectively, required time for the biological reaction of the nitrate bacteria is maintained from the injection of nitrate bacteria to solidification, thereby providing advantageous conditions for the propagation of the nitrate bacteria. In this way, there is no problem for the increase of the volume of the powdery wastes formed by the addition of inhibitor for the effect of oxidizable material. Further, heating upon solidification which is indispensable so far is no more necessary to simplify the facility and the operation. Furthermore, the solidification inhibiting material can be reduced stably and reliably under the same operation conditions even if the composition of the liquid wastes is charged or varied. (Kamimura, M.)

  9. Effects of hydrologic, biological, and environmental processes on sources and concentrations of fecal bacteria in the Cuyahoga River, with implications for management of recreational waters in Summit and Cuyahoga Counties, Ohio

    Science.gov (United States)

    Myers, Donna N.; Koltun, G.F.; Francy, Donna S.

    1998-01-01

    Discharges of fecal bacteria (fecal coliform bacteria and Escherichia coli ) to the middle main stem of the Cuyahoga River from storm water, combined sewers, and incompletely disinfected wastewater have resulted in frequent exceedances of bacteriological water-quality standards in a 23-mile reach of the river that flows through the Cuyahoga Valley National Recreation Area. Contamination of the middle main stem of the Cuyahoga River by bacteria of fecal origin and subsequent transport to downstream areas where water-contact recreation is an important use of the river are a concern because of the potential public-health risk from the presence of enteric pathogens. Independent field investigations of bacterial decay, dilution, dispersion, transport, and sources, and bacterial contamination of streambed sediments, were completed in 1991-93 during periods of rainfall and runoff. The highest concentration of fecal coliform bacteria observed in the middle main stem during three transport studies exceeded the single-sample fecal coliform standard applicable to primary-contact recreation by a factor of approximately 1,300 and exceeded the Escherichia coli standard by a factor of approximately 8,000. The geometric-mean concentrations of fecal bacteria in the middle main stem were 6.7 to 12.3 times higher than geometric-mean concentrations in the monitored tributaries, and 1.8 to 7.0 times larger than the geometric-mean concentrations discharged from the Akron Water Pollution Control Station. Decay rates of fecal bacteria measured in field studies in 1992 ranged from 0.0018 per hour to 0.0372 per hour for fecal coliform bacteria and from 0.0022 per hour to 0.0407 per hour for Escherichia coli. Most of the decay rates measured in June and August were significantly higher than decay rates measured in April and October. Results of field studies demonstrated that concentrations of fecal coliform bacteria were 1.2 to 58 times higher in streambed sediments than in the overlying

  10. Crossing Boundaries in Undergraduate Biology Education

    Science.gov (United States)

    Vanderklein, Dirk; Munakata, Mika; McManus, Jason

    2016-01-01

    In an effort to make mathematics relevant to biology students, the authors developed two modules that sought to integrate mathematics and ecology instruction to differing degrees. The modules were developed by a team of biology and mathematics educators and were implemented in an ecology course using three different instructional methods for three…

  11. Impact of Thermodynamic Principles in Systems Biology

    NARCIS (Netherlands)

    Heijnen, J.J.

    2010-01-01

    It is shown that properties of biological systems which are relevant for systems biology motivated mathematical modelling are strongly shaped by general thermodynamic principles such as osmotic limit, Gibbs energy dissipation, near equilibria and thermodynamic driving force. Each of these aspects

  12. Exemplary Programs in Secondary School Biology.

    Science.gov (United States)

    McComas, William F.; Penick, John E.

    1989-01-01

    Summarizes 10 exemplary programs which address topics on individualized biology, a modified team approach, limnology, physical anthropology, the relevance of biology to society, ecology, and health. Provides names and addresses of contact persons for further information. Units cover a broad range of abilities and activities. (RT)

  13. Sphingosine kinase 1 is a relevant molecular target in gastric cancer

    DEFF Research Database (Denmark)

    Fuereder, Thorsten; Hoeflmayer, Doris; Jaeger-Lansky, Agnes

    2011-01-01

    Sphingosine kinase 1 (Sphk1), a lipid kinase implicated in cell transformation and tumor growth, is overexpressed in gastric cancer and is linked with a poor prognosis. The biological relevance of Sphk1 expression in gastric cancer is unclear. Here, we studied the functional significance of Sphk1...... as a novel molecular target for gastric cancer by using an antisense oligonucleotide approach in vitro and in vivo. Gastric cancer cell lines (MKN28 and N87) were treated with Sphk1 with locked nucleic acid-antisense oligonucleotides (LNA-ASO). Sphk1 target regulation, cell growth, and apoptosis were...... assessed for single-agent Sphk1 LNA-ASO and for combinations with doxorubicin. Athymic nude mice xenografted with gastric cancer cells were treated with Sphk1 LNA and assessed for tumor growth and Sphk1 target regulation, in vivo. In vitro, nanomolar concentrations of Sphk1 LNA-ASO induced an approximately...

  14. Biological trade and markets.

    Science.gov (United States)

    Hammerstein, Peter; Noë, Ronald

    2016-02-05

    Cooperation between organisms can often be understood, like trade between merchants, as a mutually beneficial exchange of services, resources or other 'commodities'. Mutual benefits alone, however, are not sufficient to explain the evolution of trade-based cooperation. First, organisms may reject a particular trade if another partner offers a better deal. Second, while human trade often entails binding contracts, non-human trade requires unwritten 'terms of contract' that 'self-stabilize' trade and prevent cheating even if all traders strive to maximize fitness. Whenever trading partners can be chosen, market-like situations arise in nature that biologists studying cooperation need to account for. The mere possibility of exerting partner choice stabilizes many forms of otherwise cheatable trade, induces competition, facilitates the evolution of specialization and often leads to intricate forms of cooperation. We discuss selected examples to illustrate these general points and review basic conceptual approaches that are important in the theory of biological trade and markets. Comparing these approaches with theory in economics, it turns out that conventional models-often called 'Walrasian' markets-are of limited relevance to biology. In contrast, early approaches to trade and markets, as found in the works of Ricardo and Cournot, contain elements of thought that have inspired useful models in biology. For example, the concept of comparative advantage has biological applications in trade, signalling and ecological competition. We also see convergence between post-Walrasian economics and biological markets. For example, both economists and biologists are studying 'principal-agent' problems with principals offering jobs to agents without being sure that the agents will do a proper job. Finally, we show that mating markets have many peculiarities not shared with conventional economic markets. Ideas from economics are useful for biologists studying cooperation but need

  15. [Possibility of the spectral analysis of heterogeneous biological systems. The determination of the mycelium concentration of Actinomyces aureofaciens, a producer of tetracycline, cultured on a medium with corn meal].

    Science.gov (United States)

    Korolev, Iu N; Slugina, M D; Makarevich, V G; Telegin, N L

    1979-03-01

    A possibility of using spectroscopy of attenuated total reflection in the IR region for analysis of the heterogenic system consisting of the microorganisms and plant cells is discussed. The method of spectroscopy is proposed for estimating the mycelium concentration of Act. aureofaciens producing tetracycline in the presence of corn meal in the medium. The experimental data confirming this possibility are presented. The peculiar properties of the spectral analysis under these particular conditions are discussed. It is supposed that the method may be used for analysis of heterogenous systems including other microorganisms.

  16. Marine biology

    International Nuclear Information System (INIS)

    Thurman, H.V.; Webber, H.H.

    1984-01-01

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index

  17. Increasing the biological value of dietary cutlets

    OpenAIRE

    SYZDYKOVA L.S.; DIKHANBAYEVA F.T.; BAZYLHANOVA E.CH

    2015-01-01

    Relevance of work: meat products are the main source of the proteins, necessary for activity of the person. In this article is determined the biological value of the cutlets with dietary properties. The purpose of this work is development of the production technology of dietary cutlets in branches of public catering and determination of their biological value. As a result of work dietary cutlets with the increased biological value due to addition of oatmeal are received.

  18. Statistical investigations of SO2 and O3 concentrations in polluted areas in Southern Saxonia

    International Nuclear Information System (INIS)

    Rolle, W.; Ratzlaff, U.

    1991-01-01

    By means of some measuring values, mean hourly values of ozone and sulfur dioxide concentrations in the form of exponential-type probability density distributions are presented. This has essential advantages as compared to the usual form of indicating environmental data. Obtained is a mathematical ''formula'' describing a course in the entire range of the measured values and which can be integrated, for instance, within computer programs modelling propagation and conversion processes (especially also for sensitivity analyses). Any given percentile values can be calculated by approximation, or the probability of the incidence of extreme values of particualr biological relevance (concentration or dose) is estimated. Extreme values are also calculated by means of extremum statistics according to GUMBEL. The paper demonstrates the achievable degree of adaptation and possible applications in biology and ecology. (orig./UWA) [de

  19. Assessing the relevance of ecotoxicological studies for regulatory decision making.

    Science.gov (United States)

    Rudén, Christina; Adams, Julie; Ågerstrand, Marlene; Brock, Theo Cm; Poulsen, Veronique; Schlekat, Christian E; Wheeler, James R; Henry, Tala R

    2017-07-01

    Regulatory policies in many parts of the world recognize either the utility of or the mandate that all available studies be considered in environmental or ecological hazard and risk assessment (ERA) of chemicals, including studies from the peer-reviewed literature. Consequently, a vast array of different studies and data types need to be considered. The first steps in the evaluation process involve determining whether the study is relevant to the ERA and sufficiently reliable. Relevance evaluation is typically performed using existing guidance but involves application of "expert judgment" by risk assessors. In the present paper, we review published guidance for relevance evaluation and, on the basis of the practical experience within the group of authors, we identify additional aspects and further develop already proposed aspects that should be considered when conducting a relevance assessment for ecotoxicological studies. From a regulatory point of view, the overarching key aspect of relevance concerns the ability to directly or indirectly use the study in ERA with the purpose of addressing specific protection goals and ultimately regulatory decision making. Because ERA schemes are based on the appropriate linking of exposure and effect estimates, important features of ecotoxicological studies relate to exposure relevance and biological relevance. Exposure relevance addresses the representativeness of the test substance, environmental exposure media, and exposure regime. Biological relevance deals with the environmental significance of the test organism and the endpoints selected, the ecological realism of the test conditions simulated in the study, as well as a mechanistic link of treatment-related effects for endpoints to the protection goal identified in the ERA. In addition, uncertainties associated with relevance should be considered in the assessment. A systematic and transparent assessment of relevance is needed for regulatory decision making. The relevance

  20. The Improved Relevance Voxel Machine

    DEFF Research Database (Denmark)

    Ganz, Melanie; Sabuncu, Mert; Van Leemput, Koen

    The concept of sparse Bayesian learning has received much attention in the machine learning literature as a means of achieving parsimonious representations of features used in regression and classification. It is an important family of algorithms for sparse signal recovery and compressed sensing....... Hence in its current form it is reminiscent of a greedy forward feature selection algorithm. In this report, we aim to solve the problems of the original RVoxM algorithm in the spirit of [7] (FastRVM).We call the new algorithm Improved Relevance Voxel Machine (IRVoxM). Our contributions...... and enables basis selection from overcomplete dictionaries. One of the trailblazers of Bayesian learning is MacKay who already worked on the topic in his PhD thesis in 1992 [1]. Later on Tipping and Bishop developed the concept of sparse Bayesian learning [2, 3] and Tipping published the Relevance Vector...

  1. Familial Resemblance for Serum Metabolite Concentrations

    NARCIS (Netherlands)

    Draisma, H.H.M.; Beekman, M.; Pool, R.; van Ommen, G.J.B; Vaarhorst, A.A.M.; de Craen, A.J.; Willemsen, G.; Slagboom, P.E.; Boomsma, D.I.

    2013-01-01

    Metabolomics is the comprehensive study of metabolites, which are the substrates, intermediate, and end products of cellular metabolism. The heritability of the concentrations of circulating metabolites bears relevance for evaluating their suitability as biomarkers for disease. We report aspects of

  2. Structural Biology Fact Sheet

    Science.gov (United States)

    ... NIGMS NIGMS Home > Science Education > Structural Biology Structural Biology Tagline (Optional) Middle/Main Content Area PDF Version (688 KB) Other Fact Sheets What is structural biology? Structural biology is the study of how biological ...

  3. Biologic Constraints on Modelling Virus Assembly

    Directory of Open Access Journals (Sweden)

    Robert L. Garcea

    2008-01-01

    Full Text Available The mathematic modelling of icosahedral virus assembly has drawn increasing interest because of the symmetric geometry of the outer shell structures. Many models involve equilibrium expressions of subunit binding, with reversible subunit additions forming various intermediate structures. The underlying assumption is that a final lowest energy state drives the equilibrium toward assembly. In their simplest forms, these models have explained why high subunit protein concentrations and strong subunit association constants can result in kinetic traps forming off pathway partial and aberrant structures. However, the cell biology of virus assembly is exceedingly complex. The biochemistry and biology of polyoma and papillomavirus assembly described here illustrates many of these specific issues. Variables include the use of cellular ‘chaperone’ proteins as mediators of assembly fidelity, the coupling of assembly to encapsidation of a specific nucleic acid genome, the use of cellular structures as ‘workbenches’ upon which assembly occurs, and the underlying problem of making a capsid structure that is metastable and capable of rapid disassembly upon infection. Although formidable to model, incorporating these considerations could advance the relevance of mathematical models of virus assembly to the real world.

  4. Probabilistic biological network alignment.

    Science.gov (United States)

    Todor, Andrei; Dobra, Alin; Kahveci, Tamer

    2013-01-01

    Interactions between molecules are probabilistic events. An interaction may or may not happen with some probability, depending on a variety of factors such as the size, abundance, or proximity of the interacting molecules. In this paper, we consider the problem of aligning two biological networks. Unlike existing methods, we allow one of the two networks to contain probabilistic interactions. Allowing interaction probabilities makes the alignment more biologically relevant at the expense of explosive growth in the number of alternative topologies that may arise from different subsets of interactions that take place. We develop a novel method that efficiently and precisely characterizes this massive search space. We represent the topological similarity between pairs of aligned molecules (i.e., proteins) with the help of random variables and compute their expected values. We validate our method showing that, without sacrificing the running time performance, it can produce novel alignments. Our results also demonstrate that our method identifies biologically meaningful mappings under a comprehensive set of criteria used in the literature as well as the statistical coherence measure that we developed to analyze the statistical significance of the similarity of the functions of the aligned protein pairs.

  5. Biology Branch

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, W F

    1974-12-31

    Progress is reported on the following studies in biochemistry and molecular biology: study of long pyrimidine polynucleotides in DNA; isolation of thymine dimers from Schizosaccharomyces pombe; thermal stability of high molecular weight RNA; nucleases of Micrococcus radiodurans; effect of ionizing radiation on M. radiodurans cell walls and cell membranes; chemical modification of nucleotides; exonucleases of M. radiodurans; and enzymatic basis of repair of radioinduced damage in M. radiodurans. Genetics, development, and population studies include repair pathways and mutation induction in yeast; induction of pure mutant clones in yeast; radiosensitivity of bacteriophage T4; polyacrylamide gel electrophoresis of bacteriophage T4; radiation genetics of Dahibominus; and radiation studies on bitting flies. (HLW)

  6. Biological biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Jorge-Herrero, E. [Servicio de Cirugia Experimental. Clinica Puerta de Hierro, Madrid (Spain)

    1997-05-01

    There are a number of situations in which substances of biological origin are employed as biomaterials. Most of them are macromolecules derived from isolated connective tissue or the connective tissue itself in membrane form, in both cases, the tissue can be used in its natural form or be chemically treated. In other cases, certain blood vessels can be chemically pretreated and used as vascular prostheses. Proteins such as albumin, collagen and fibrinogen are employed to coat vascular prostheses. Certain polysaccharides have also been tested for use in controlled drug release systems. Likewise, a number of tissues, such as dura mater, bovine pericardium, procine valves and human valves, are used in the preparation of cardiac prostheses. We also use veins from animals or humans in arterial replacement. In none of these cases are the tissues employed dissimilar to the native tissues as they have been chemically modified, becoming a new bio material with different physical and biochemical properties. In short, we find that natural products are being utilized as biomaterials and must be considered as such; thus, it is necessary to study both their chemicobiological and physicomechanical properties. In the present report, we review the current applications, problems and future prospects of some of these biological biomaterials. (Author) 84 refs.

  7. Microdosing: Concept, application and relevance

    Directory of Open Access Journals (Sweden)

    Tushar Tewari

    2010-01-01

    Full Text Available The use of microdose pharmacokinetic studies as an essential tool in drug development is still to catch on. While this approach promises potential cost savings and a quantum leap in efficiencies of the drug development process, major hurdles still need to be overcome before the technique becomes commonplace and part of routine practice. Clear regulations in Europe and the USA have had an enabling effect. The lack of enabling provisions for microdosing studies in Indian regulation, despite low risk and manifest relevance for the local drug development industry, is inconsistent with the country′s aspirations to be among the leaders in pharmaceutical research.

  8. Dose-dependent cytotoxicity of clinically relevant cobalt nanoparticles and ions on macrophages in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Young-Min; Xia Zhidao; Glyn-Jones, Sion; Beard, David; Gill, Harinderjit S; Murray, David W, E-mail: young-min.kwon@ndos.ox.ac.u [Nuffield Department of Orthopaedic Surgery, University of Oxford, Oxford OX3 7LD (United Kingdom)

    2009-04-15

    Despite the satisfactory short-term implant survivorship of metal-on-metal hip resurfacing arthroplasty, periprosthetic soft-tissue masses such as pseudotumours are being increasingly reported. Cytotoxic effects of cobalt or chromium have been suggested to play a role in its aetiology. The aim of this study was to investigate the effects of clinically relevant metal nanoparticles and ions on the viability of macrophages in vitro. A RAW 264.7 murine macrophage cell line was cultured in the presence of either: (1) cobalt, chromium and titanium nanoparticles sized 30-35 nm; or (2) cobalt sulphate and chromium chloride. Two methods were used to quantify cell viability: Alamar Blue assay and Live/Dead assay. The cytotoxicity was observed only with cobalt. Cobalt nanoparticles and ions demonstrated dose-dependent cytotoxic effects on macrophages in vitro: the cytotoxic concentrations of nanoparticles and ions were 1 x 10{sup 12} particles ml{sup -1} and 1000 {mu}M, respectively. The high concentration of cobalt nanoparticles required for cytotoxicity of macrophages in vitro suggests that increased production of cobalt nanoparticles in vivo, due to excessive MoM implant wear, may lead to local adverse biological effects. Therefore, cytotoxicity of high concentrations of metal nanoparticles phagocytosed by macrophages located in the periprosthetic tissues may be an important factor in pathogenesis of pseudotumours.

  9. Ecological principles relevant to nuclear war

    International Nuclear Information System (INIS)

    Hutchinson, T.C.; Cropper, W.P. Jr.; Grover, H.D.

    1985-01-01

    The ecological principles outlined are very basic ones; the authors anticipate a readership trained in a broad range of disciplines, including those unfamiliar with the academic discipline of ecology. The authors include substantial discussion on ecophysiology (i.e., the responses of organisms to their environment) because this is relevant to the new understanding of the potential climatic consequences of nuclear war. In particular, the physiological sensitivity of organisms to reduced levels of light and temperature are a key part of the analysis of the potential ecological effects and agricultural effects of nuclear war. Much of the ecological analysis has been organized around major biological units called biomes. The authors describe the biome concept and discuss some of the environmental-climatic factors that are believed to control biome distribution. Emphasis is given to plants because of their controlling influence on ecosystem functions through their role as primary producers. Future reports are needed to address more fully the potential effects on animals. Much more research needs to be done on both plant and animal responses to the types of perturbations possible for the aftermath of a nuclear war. Another important element for analysis of the potential ecological consequences of nuclear war concerns recovery processes. As the post-nuclear war environmental extremes ameliorate, ecological communities in devastated regions would begin to reorganize. It is not possible to predict the course of such a succession precisely, but some principles concerning post-perturbation replacement (such as seed banks and germination), relevant successional patterns, and organism strategies are discussed

  10. Quantification of biologically effective environmental UV irradiance

    Science.gov (United States)

    Horneck, G.

    To determine the impact of environmental UV radiation on human health and ecosystems demands monitoring systems that weight the spectral irradiance according to the biological responses under consideration. In general, there are three different approaches to quantify a biologically effective solar irradiance: (i) weighted spectroradiometry where the biologically weighted radiometric quantities are derived from spectral data by multiplication with an action spectrum of a relevant photobiological reaction, e.g. erythema, DNA damage, skin cancer, reduced productivity of terrestrial plants and aquatic foodweb; (ii) wavelength integrating chemical-based or physical dosimetric systems with spectral sensitivities similar to a biological response curve; and (iii) biological dosimeters that directly weight the incident UV components of sunlight in relation to the effectiveness of the different wavelengths and to interactions between them. Most biological dosimeters, such as bacteria, bacteriophages, or biomolecules, are based on the UV sensitivity of DNA. If precisely characterized, biological dosimeters are applicable as field and personal dosimeters.

  11. Biological effects

    International Nuclear Information System (INIS)

    Trott, K.R.

    1973-01-01

    Following an introduction into the field of cellular radiation effect considering the most important experimental results, the biological significance of the colony formation ability is brought out. The inactivation concept of stem cells does not only prove to be good, according to the present results, in the interpretation of the pathogenesis of acute radiation effects on moult tissue, it also enables chronicle radiation injuries to be interpreted through changes in the fibrous part of the organs. Radiation therapy of tumours can also be explained to a large extent by the radiation effect on the unlimited reproductiveness of tumour cells. The more or less similar dose effect curves for healthy and tumour tissue in practice lead to intermittent irradiation. The dependence of the intermittent doses and intervals on factors such as Elkind recovery, synchronisation, redistribution, reoxygenation, repopulation and regeneration are reviewed. (ORU/LH) [de

  12. Elemental and isotopic imaging of biological samples using NanoSIMS.

    Science.gov (United States)

    Kilburn, Matt R; Clode, Peta L

    2014-01-01

    With its low detection limits and the ability to analyze most of the elements in the periodic table, secondary ion mass spectrometry (SIMS) represents one of the most versatile in situ analytical techniques available, and recent developments have resulted in significant advantages for the use of imaging mass spectrometry in biological and biomedical research. Increases in spatial resolution and sensitivity allow detailed interrogation of samples at relevant scales and chemical concentrations. Advances in dynamic SIMS, specifically with the advent of NanoSIMS, now allow the tracking of stable isotopes within biological systems at subcellular length scales, while static SIMS combines subcellular imaging with molecular identification. In this chapter, we present an introduction to the SIMS technique, with particular reference to NanoSIMS, and discuss its application in biological and biomedical research.

  13. Students' Personal Connection with Science: Investigating the Multidimensional Phenomenological Structure of Self-Relevance

    Science.gov (United States)

    Hartwell, Matthew; Kaplan, Avi

    2018-01-01

    This paper presents findings from a two-phase mixed methods study investigating the phenomenological structure of self-relevance among ninth-grade junior high school biology students (Phase 1: N = 118; Phase 2: N = 139). We begin with a phenomenological multidimensional definition of self-relevance as comprising three dimensions: the academic…

  14. Biophysical characterization of the Lactobacillus delbrueckii subsp. bulgaricus membrane during cold and osmotic stress and its relevance for cryopreservation.

    Science.gov (United States)

    Meneghel, Julie; Passot, Stéphanie; Dupont, Sébastien; Fonseca, Fernanda

    2017-02-01

    Freezing lactic acid bacteria often leads to cell death and loss of technological properties. Our objective was to provide an in-depth characterization of the biophysical properties of the Lactobacillus delbrueckii subsp. bulgaricus membrane in relation to its freeze resistance. Freezing was represented as a combination of cold and osmotic stress. This work investigated the relative incidence of increasing sucrose concentrations coupled or not with subzero temperatures without ice nucleation on the biological and biophysical responses of two strains with different membrane fatty acid compositions and freeze resistances. Following exposure of bacterial cells to the highest sucrose concentration, the sensitive strain exhibited a survival rate of less than 10 % and 5 h of acidifying activity loss. Similar biological activity losses were observed upon freeze-thawing and after osmotic treatment for each strain thus highlighting osmotic stress as the main source of cryoinjury. The direct measurement of membrane fluidity by fluorescence anisotropy was linked to membrane lipid organization characterized by FTIR spectroscopy. Both approaches made it possible to investigate the specific contributions of the membrane core and the bilayer external surface to cell degradation caused by cold and osmotic stress. Cold-induced membrane rigidification had no significant implication on bacterial freeze-thaw resistance. Interactions between extracellular sucrose and membrane phospholipid headgroups under osmotic stress were also observed. Such interactions were more evident in the sensitive strain and when increasing sucrose concentration, thus suggesting membrane permeabilization. The relevance of biophysical properties for elucidating mechanisms of cryoinjury and cryoprotection is discussed.

  15. Biologics in pediatric psoriasis - efficacy and safety.

    Science.gov (United States)

    Dogra, Sunil; Mahajan, Rahul

    2018-01-01

    Childhood psoriasis is a special situation that is a management challenge for the treating dermatologist. As is the situation with traditional systemic agents, which are commonly used in managing severe psoriasis in children, the biologics are being increasingly used in the recalcitrant disease despite limited data on long term safety. Areas covered: We performed an extensive literature search to collect evidence-based data on the use of biologics in pediatric psoriasis. The relevant literature published from 2000 to September 2017 was obtained from PubMed, using the MeSH words 'biologics', 'biologic response modifiers' and 'treatment of pediatric/childhood psoriasis'. All clinical trials, randomized double-blind or single-blind controlled trials, open-label studies, retrospective studies, reviews, case reports and letters concerning the use of biologics in pediatric psoriasis were screened. Articles covering the use of biologics in pediatric psoriasis were screened and reference lists in the selected articles were scrutinized to identify other relevant articles that had not been found in the initial search. Articles without relevant information about biologics in general (e.g. its mechanism of action, pharmacokinetics and adverse effects) and its use in psoriasis in particular were excluded. We screened 427 articles and finally selected 41 relevant articles. Expert opinion: The available literature on the use of biologics such as anti-tumor necrosis factor (TNF)-α agents, and anti-IL-12/23 agents like ustekinumab suggests that these are effective and safe in managing severe pediatric psoriasis although there is an urgent need to generate more safety data. Dermatologists must be careful about the potential adverse effects of the biologics before administering them to children with psoriasis. It is likely that with rapidly evolving scenario of biologics in psoriasis, these will prove to be very useful molecules particularly in managing severe and recalcitrant

  16. Interactive Effects of Working Memory Self-Regulatory Ability and Relevance Instructions on Text Processing

    Science.gov (United States)

    Hamilton, Nancy Jo

    2012-01-01

    Reading is a process that requires the enactment of many cognitive processes. Each of these processes uses a certain amount of working memory resources, which are severely constrained by biology. More efficiency in the function of working memory may mediate the biological limits of same. Reading relevancy instructions may be one such method to…

  17. Neutron Scattering in Biology Techniques and Applications

    CERN Document Server

    Fitter, Jörg; Katsaras, John

    2006-01-01

    The advent of new neutron facilities and the improvement of existing sources and instruments world wide supply the biological community with many new opportunities in the areas of structural biology and biological physics. The present volume offers a clear description of the various neutron-scattering techniques currently being used to answer biologically relevant questions. Their utility is illustrated through examples by some of the leading researchers in the field of neutron scattering. This volume will be a reference for researchers and a step-by-step guide for young scientists entering the field and the advanced graduate student.

  18. Other relevant numerical modelling papers

    International Nuclear Information System (INIS)

    Chartier, M.

    1989-01-01

    The ocean modelling is a rapidly evolving science and a large number of results have been published. Several categories of papers are of particular interest for this review: the papers published by the international atomic institutions, such as the NEA (for the CRESP or Subseabed Programs), the IAEA (for example the Safety Series, the Technical Report Series or the TECDOC), and the ICRP, and the papers concerned by more fundamental research, which are published in specific scientific literature. This paper aims to list some of the most relevant publications for the CRESP purposes. It means by no way to be exhaustive, but informative on the incontestable progress recently achieved in that field. One should note that some of these papers are so recent that their final version has not yet been published

  19. Industrial relevance of thermophilic Archaea.

    Science.gov (United States)

    Egorova, Ksenia; Antranikian, Garabed

    2005-12-01

    The dramatic increase of newly isolated extremophilic microorganisms, analysis of their genomes and investigations of their enzymes by academic and industrial laboratories demonstrate the great potential of extremophiles in industrial (white) biotechnology. Enzymes derived from extremophiles (extremozymes) are superior to the traditional catalysts because they can perform industrial processes even under harsh conditions, under which conventional proteins are completely denatured. In particular, enzymes from thermophilic and hyperthermophilic Archaea have industrial relevance. Despite intensive investigations, our knowledge of the structure-function relationships of their enzymes is still limited. Information concerning the molecular properties of their enzymes and genes has to be obtained to be able to understand the mechanisms that are responsible for catalytic activity and stability at the boiling point of water.

  20. The Relevance of Hegel's Logic

    Directory of Open Access Journals (Sweden)

    John W Burbidge

    2007-12-01

    Full Text Available Hegel defines his Logic as the science that thinks about thinking.nbsp; But when we interpret that work as outlining what happens when we reason we are vulnerable to Fregersquo;s charge of psychologism.nbsp; I use Hegelrsquo;s tripartite distinction among understanding, dialectical and speculative reason as operations of pure thought to suggest how thinking can work with objective concepts.nbsp; In the last analysis, however, our ability to move from the subjective contingency of representations and ideas to the pure concepts we think develops from mechanical memory, which separates sign from sense so hat we can focus simply on the latter.nbsp; By becoming aware of the connections that underlie our thinking processes we may be able to both move beyond the abstractions of symbolic logic and clarify what informal logicians call relevance.

  1. Creating biological nanomaterials using synthetic biology

    International Nuclear Information System (INIS)

    Rice, MaryJoe K; Ruder, Warren C

    2014-01-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems. (review)

  2. Creating biological nanomaterials using synthetic biology.

    Science.gov (United States)

    Rice, MaryJoe K; Ruder, Warren C

    2014-02-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems.

  3. Interaction of dermatologically relevant nanoparticles with skin cells and skin

    Directory of Open Access Journals (Sweden)

    Annika Vogt

    2014-12-01

    Full Text Available The investigation of nanoparticle interactions with tissues is complex. High levels of standardization, ideally testing of different material types in the same biological model, and combinations of sensitive imaging and detection methods are required. Here, we present our studies on nanoparticle interactions with skin, skin cells, and biological media. Silica, titanium dioxide and silver particles were chosen as representative examples for different types of skin exposure to nanomaterials, e.g., unintended environmental exposure (silica versus intended exposure through application of sunscreen (titanium dioxide or antiseptics (silver. Because each particle type exhibits specific physicochemical properties, we were able to apply different combinations of methods to examine skin penetration and cellular uptake, including optical microscopy, electron microscopy, X-ray microscopy on cells and tissue sections, flow cytometry of isolated skin cells as well as Raman microscopy on whole tissue blocks. In order to assess the biological relevance of such findings, cell viability and free radical production were monitored on cells and in whole tissue samples. The combination of technologies and the joint discussion of results enabled us to look at nanoparticle–skin interactions and the biological relevance of our findings from different angles.

  4. Optimal concentrations in transport systems

    Science.gov (United States)

    Jensen, Kaare H.; Kim, Wonjung; Holbrook, N. Michele; Bush, John W. M.

    2013-01-01

    Many biological and man-made systems rely on transport systems for the distribution of material, for example matter and energy. Material transfer in these systems is determined by the flow rate and the concentration of material. While the most concentrated solutions offer the greatest potential in terms of material transfer, impedance typically increases with concentration, thus making them the most difficult to transport. We develop a general framework for describing systems for which impedance increases with concentration, and consider material flow in four different natural systems: blood flow in vertebrates, sugar transport in vascular plants and two modes of nectar drinking in birds and insects. The model provides a simple method for determining the optimum concentration copt in these systems. The model further suggests that the impedance at the optimum concentration μopt may be expressed in terms of the impedance of the pure (c = 0) carrier medium μ0 as μopt∼2αμ0, where the power α is prescribed by the specific flow constraints, for example constant pressure for blood flow (α = 1) or constant work rate for certain nectar-drinking insects (α = 6). Comparing the model predictions with experimental data from more than 100 animal and plant species, we find that the simple model rationalizes the observed concentrations and impedances. The model provides a universal framework for studying flows impeded by concentration, and yields insight into optimization in engineered systems, such as traffic flow. PMID:23594815

  5. Electron Transfer in Chemistry and Biology - The Primary Events in ...

    Indian Academy of Sciences (India)

    transfers, occurs in a cascade in many biological processes, including photosynthesis. ... the model reactions of photosynthetic ... biological relevance. GENERAL I ARTICLE of electrons, respectively. This has entirely changed the earlier framework of interpreting reactions in chemistry and biology. This shift in emphasis ...

  6. IQ Predicts Biological Motion Perception in Autism Spectrum Disorders

    Science.gov (United States)

    Rutherford, M. D.; Troje, Nikolaus F.

    2012-01-01

    Biological motion is easily perceived by neurotypical observers when encoded in point-light displays. Some but not all relevant research shows significant deficits in biological motion perception among those with ASD, especially with respect to emotional displays. We tested adults with and without ASD on the perception of masked biological motion…

  7. Bridging Physics and Biology Using Resistance and Axons

    Science.gov (United States)

    Dyer, Joshua M.

    2014-01-01

    When teaching physics, it is often difficult to get biology-oriented students to see the relevance of physics. A complaint often heard is that biology students are required to take physics for the Medical College Admission Test (MCAT) as part of a "weeding out" process, but that they don't feel like they need physics for biology. Despite…

  8. Impact of calcium and TOC on biological acidification assessment in Norwegian rivers.

    Science.gov (United States)

    Schneider, Susanne C

    2011-02-15

    Acidification continues to be a major impact in freshwaters of northern Europe, and the biotic response to chemical recovery from acidification is often not a straightforward process. The focus on biological recovery is relevant within the context of the EU Water Framework Directive, where a biological monitoring system is needed that detects differences in fauna and flora compared to undisturbed reference conditions. In order to verify true reference sites for biological analyses, expected river pH is modeled based on Ca and TOC, and 94% of variability in pH at reference sites is explained by Ca alone, while 98% is explained by a combination of Ca and TOC. Based on 59 samples from 28 reference sites, compared to 547 samples from 285 non-reference sites, the impact of calcium and total organic carbon (TOC) on benthic algae species composition, expressed as acidification index periphyton (AIP), is analyzed. Rivers with a high Ca concentration have a naturally higher AIP, and TOC affects reference AIP only at low Ca concentrations. Four biological river types are needed for assessment of river acidification in Norway based on benthic algae: very calcium-poor, humic rivers (CaTOC>2 mg/l); very calcium-poor, clear rivers (CaTOC4 mg/l). A biological assessment system for river acidification in Norway based on benthic algae is presented, following the demands of the Water Framework Directive. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Synthetic Biology and Personalized Medicine

    Science.gov (United States)

    Jain, K.K.

    2013-01-01

    Synthetic biology, application of synthetic chemistry to biology, is a broad term that covers the engineering of biological systems with structures and functions not found in nature to process information, manipulate chemicals, produce energy, maintain cell environment and enhance human health. Synthetic biology devices contribute not only to improve our understanding of disease mechanisms, but also provide novel diagnostic tools. Methods based on synthetic biology enable the design of novel strategies for the treatment of cancer, immune diseases metabolic disorders and infectious diseases as well as the production of cheap drugs. The potential of synthetic genome, using an expanded genetic code that is designed for specific drug synthesis as well as delivery and activation of the drug in vivo by a pathological signal, was already pointed out during a lecture delivered at Kuwait University in 2005. Of two approaches to synthetic biology, top-down and bottom-up, the latter is more relevant to the development of personalized medicines as it provides more flexibility in constructing a partially synthetic cell from basic building blocks for a desired task. PMID:22907209

  10. A Brief Introduction to Chinese Biological Biological

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Chinese Biological Abstracts sponsored by the Library, the Shanghai Institutes for Biological Sciences, the Biological Documentation and Information Network, all of the Chinese Academy of Sciences, commenced publication in 1987 and was initiated to provide access to the Chinese information in the field of biology.

  11. Biologics in spine arthrodesis.

    Science.gov (United States)

    Kannan, Abhishek; Dodwad, Shah-Nawaz M; Hsu, Wellington K

    2015-06-01

    Spine fusion is a tool used in the treatment of spine trauma, tumors, and degenerative disorders. Poor outcomes related to failure of fusion, however, have directed the interests of practitioners and scientists to spinal biologics that may impact fusion at the cellular level. These biologics are used to achieve successful arthrodesis in the treatment of symptomatic deformity or instability. Historically, autologous bone grafting, including iliac crest bong graft harvesting, had represented the gold standard in spinal arthrodesis. However, due to concerns over potential harvest site complications, supply limitations, and associated morbidity, surgeons have turned to other bone graft options known for their osteogenic, osteoinductive, and/or osteoconductive properties. Current bone graft selection includes autograft, allograft, demineralized bone matrix, ceramics, mesenchymal stem cells, and recombinant human bone morphogenetic protein. Each pose their respective advantages and disadvantages and are the focus of ongoing research investigating the safety and efficacy of their use in the setting of spinal fusion. Rh-BMP2 has been plagued by issues of widespread off-label use, controversial indications, and a wide range of adverse effects. The risks associated with high concentrations of exogenous growth factors have led to investigational efforts into nanotechnology and its application in spinal arthrodesis through the binding of endogenous growth factors. Bone graft selection remains critical to successful fusion and favorable patient outcomes, and orthopaedic surgeons must be educated on the utility and limitations of various biologics in the setting of spine arthrodesis.

  12. Role of accelerator mass spectrometry in biological dosimetry

    International Nuclear Information System (INIS)

    Felton, J.S.; Turteltaub, K.W.; Frantz, C.; Vogel, J.S.; Gledhill, B.L.

    1992-01-01

    Understanding risks from exposures to carcinogens and other chemicals depends upon measurement of their dose to target tissues and their reactivity with critical macromolecules. The authors have used AMS detection of radio-isotopes to assess doses and reactivities at low, environmentally relevant doses. Several biomedical investigations show the effectiveness of quantification of biologically important events at extremely high sensitivity with AMS. Specifically, they have measured the addition of environmental carcinogens such as 2-amino-3,8-dimethylimidazo[4,5-f]-quinoaxaline (MelQx), a chemical found in cooked food, to DNA at concentrations relevant to human exposure. Other low level detection problems in biology, such as immunoassay assessment of small environmental chemicals, is being developed with attomole sensitivity. AMS also aids the assessment of genotoxic risks from chemicals by quantifying the binding of labeled chemicals to DNA. The very toxic and potent carcinogen, tetrachlorodibenzo-p-dioxin (TCDD) was assessed for DNA binding, but no detectable radiocarbon-labeled TCDD was found associated with mouse liver DNA at less than systematically toxic levels. The data indicate that a mutation mechanism does not mediate TCDD carcinogenesis

  13. Application of Biologically-Based Lumping To Investigate the ...

    Science.gov (United States)

    People are often exposed to complex mixtures of environmental chemicals such as gasoline, tobacco smoke, water contaminants, or food additives. However, investigators have often considered complex mixtures as one lumped entity. Valuable information can be obtained from these experiments, though this simplification provides little insight into the impact of a mixture's chemical composition on toxicologically-relevant metabolic interactions that may occur among its constituents. We developed an approach that applies chemical lumping methods to complex mixtures, in this case gasoline, based on biologically relevant parameters used in physiologically-based pharmacokinetic (PBPK) modeling. Inhalation exposures were performed with rats to evaluate performance of our PBPK model. There were 109 chemicals identified and quantified in the vapor in the chamber. The time-course kinetic profiles of 10 target chemicals were also determined from blood samples collected during and following the in vivo experiments. A general PBPK model was used to compare the experimental data to the simulated values of blood concentration for the 10 target chemicals with various numbers of lumps, iteratively increasing from 0 to 99. Large reductions in simulation error were gained by incorporating enzymatic chemical interactions, in comparison to simulating the individual chemicals separately. The error was further reduced by lumping the 99 non-target chemicals. Application of this biologic

  14. The relevance of "non-relevant metabolites" from plant protection products (PPPs) for drinking water: the German view.

    Science.gov (United States)

    Dieter, Hermann H

    2010-03-01

    evaluation of a "non-relevant metabolite", its HRIV is either set as 1.0 microg/l (HRIV(a)) or as 3.0 microg/l (HRIV(b)) for lifelong exposure. In case a HRIV would be exceeded, UBA recommends to keep on a precautionary action value (PAV) of 10 microg/l for each "non-relevant metabolite". The HRIV(b) is similar to the maximal value derived by application of the TTC-concept for Cramer Class III (4.5 microg/l). The HRIV(a) and the PAV are similar to values in the EU-guidance document for assessing "non-relevant metabolites" in ground water, with the important difference that the drinking water PAV is not intended to be tolerated for permanent exposure. Drinking water containing "non-relevant metabolites" below the respective HRIVs can also be considered as being sufficiently protective against toxicologically relevant oxidative transformation products which may be formed from "non-relevant metabolites" during drinking water treatment with ozone. However, even drinking water where one or several "non-relevant metabolites" are detected above substance-specific HRIVs is suited for human consumption without health risks. Only in special cases (relatively high "non-relevant metabolite" - concentrations), it could be indicated to examine the finished water for transformation products after treatment with ozone if there are no further treatment steps to eliminate or degrade polar compounds. UBA's "non-relevant metabolite-Recommendation" from April 2008 was positively picked up in 2009 by four important stakeholders in the domain of drinking water management as part of a voluntary cooperation agreement. The aim of such cooperation is to limit the transport of "non-relevant metabolites" into the drinking water to the functionally (and agriculturally) unavoidable extent and insofar to meet special precautionary demands. (c) 2009 Elsevier Inc. All rights reserved.

  15. Relevance of equilibrium in multifragmentation

    International Nuclear Information System (INIS)

    Furuta, Takuya; Ono, Akira

    2009-01-01

    The relevance of equilibrium in a multifragmentation reaction of very central 40 Ca + 40 Ca collisions at 35 MeV/nucleon is investigated by using simulations of antisymmetrized molecular dynamics (AMD). Two types of ensembles are compared. One is the reaction ensemble of the states at each reaction time t in collision events simulated by AMD, and the other is the equilibrium ensemble prepared by solving the AMD equation of motion for a many-nucleon system confined in a container for a long time. The comparison of the ensembles is performed for the fragment charge distribution and the excitation energies. Our calculations show that there exists an equilibrium ensemble that well reproduces the reaction ensemble at each reaction time t for the investigated period 80≤t≤300 fm/c. However, there are some other observables that show discrepancies between the reaction and equilibrium ensembles. These may be interpreted as dynamical effects in the reaction. The usual static equilibrium at each instant is not realized since any equilibrium ensemble with the same volume as that of the reaction system cannot reproduce the fragment observables

  16. Statistical significance versus clinical relevance.

    Science.gov (United States)

    van Rijn, Marieke H C; Bech, Anneke; Bouyer, Jean; van den Brand, Jan A J G

    2017-04-01

    In March this year, the American Statistical Association (ASA) posted a statement on the correct use of P-values, in response to a growing concern that the P-value is commonly misused and misinterpreted. We aim to translate these warnings given by the ASA into a language more easily understood by clinicians and researchers without a deep background in statistics. Moreover, we intend to illustrate the limitations of P-values, even when used and interpreted correctly, and bring more attention to the clinical relevance of study findings using two recently reported studies as examples. We argue that P-values are often misinterpreted. A common mistake is saying that P < 0.05 means that the null hypothesis is false, and P ≥0.05 means that the null hypothesis is true. The correct interpretation of a P-value of 0.05 is that if the null hypothesis were indeed true, a similar or more extreme result would occur 5% of the times upon repeating the study in a similar sample. In other words, the P-value informs about the likelihood of the data given the null hypothesis and not the other way around. A possible alternative related to the P-value is the confidence interval (CI). It provides more information on the magnitude of an effect and the imprecision with which that effect was estimated. However, there is no magic bullet to replace P-values and stop erroneous interpretation of scientific results. Scientists and readers alike should make themselves familiar with the correct, nuanced interpretation of statistical tests, P-values and CIs. © The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  17. Does relevance matter in academic policy research?

    DEFF Research Database (Denmark)

    Dredge, Dianne

    2015-01-01

    A reflection on whether relevance matters in tourism policy research. A debate among tourism scholars.......A reflection on whether relevance matters in tourism policy research. A debate among tourism scholars....

  18. Normal concentrations of heavy metals in autistic spectrum disorders.

    Science.gov (United States)

    Albizzati, A; Morè, L; Di Candia, D; Saccani, M; Lenti, C

    2012-02-01

    Autism is a neurological-psychiatric disease. In the last 20 years we witnessed a strong increase of autism diagnoses. To explain this increase, some scientists put forward the hypothesis that heavy metal intoxication may be one of the causes of autism. The origin of such an intoxication was hypothesised to be vaccines containing thimerosal as antimicrobic preservative. This preservative is mainly made up of mercury. The aim of our research was to investigate the correlation between autism and high biological concentrations of heavy metals. Seventeen autistic patients, between 6 and 16 years old (average: 11.52 DS: 3.20) (15 males and 2 females), were investigated, as well as 20 non autistic subjects from neuropsychiatric service between 6 and 16 years (average: 10.41 DS: 3.20) (15 males and 2 females). In both groups blood, urine and hair samples were analysed trough means of a semiquantitative analysis of heavy metal dosing. The metals analysed were Lead, mercury, cadmium and aluminium, since their build-up may give both neurological and psychiatric symptoms. The comparison of the mean values of the concentrations between the groups, performed with ANOVA test, has shown no statistically relevant differences. There wasn't correlation between autism and heavy metal concentration.

  19. Cisplatin Resistant Spheroids Model Clinically Relevant Survival Mechanisms in Ovarian Tumors.

    Directory of Open Access Journals (Sweden)

    Winyoo Chowanadisai

    Full Text Available The majority of ovarian tumors eventually recur in a drug resistant form. Using cisplatin sensitive and resistant cell lines assembled into 3D spheroids we profiled gene expression and identified candidate mechanisms and biological pathways associated with cisplatin resistance. OVCAR-8 human ovarian carcinoma cells were exposed to sub-lethal concentrations of cisplatin to create a matched cisplatin-resistant cell line, OVCAR-8R. Genome-wide gene expression profiling of sensitive and resistant ovarian cancer spheroids identified 3,331 significantly differentially expressed probesets coding for 3,139 distinct protein-coding genes (Fc >2, FDR < 0.05 (S2 Table. Despite significant expression changes in some transporters including MDR1, cisplatin resistance was not associated with differences in intracellular cisplatin concentration. Cisplatin resistant cells were significantly enriched for a mesenchymal gene expression signature. OVCAR-8R resistance derived gene sets were significantly more biased to patients with shorter survival. From the most differentially expressed genes, we derived a 17-gene expression signature that identifies ovarian cancer patients with shorter overall survival in three independent datasets. We propose that the use of cisplatin resistant cell lines in 3D spheroid models is a viable approach to gain insight into resistance mechanisms relevant to ovarian tumors in patients. Our data support the emerging concept that ovarian cancers can acquire drug resistance through an epithelial-to-mesenchymal transition.

  20. Breath acetone concentration; biological variability and the influence of diet

    Czech Academy of Sciences Publication Activity Database

    Španěl, Patrik; Dryahina, Kseniya; Rejšková, A.; Chippendale, T. W. E.; Smith, D.

    2011-01-01

    Roč. 32, č. 8 (2011), N23-N31 ISSN 0967-3334 R&D Projects: GA ČR GP203/09/P172 Institutional research plan: CEZ:AV0Z40400503 Keywords : acetone * breath * ketogenic diet Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.677, year: 2011

  1. Science and the struggle for relevance

    NARCIS (Netherlands)

    Hessels, L.K.|info:eu-repo/dai/nl/304832863

    2010-01-01

    This thesis deals with struggles for relevance of university researchers, their efforts to make their work correspond with ruling standards of relevance and to influence these standards. Its general research question is: How to understand changes in the struggle for relevance of Dutch academic

  2. The Personal Relevance of the Social Studies.

    Science.gov (United States)

    VanSickle, Ronald L.

    1990-01-01

    Conceptualizes a personal-relevance framework derived from Ronald L. VanSickle's five areas of life integrated with four general motivating goals from Abraham Maslow's hierarchy of needs and Richard and Patricia Schmuck's social motivation theory. Illustrates ways to apply the personal relevance framework to make social studies more relevant to…

  3. The Development of Relevance in Information Retrieval

    Directory of Open Access Journals