WorldWideScience

Sample records for biological interactions potential

  1. Orchid-pollinator interactions and potential vulnerability to biological invasion.

    Science.gov (United States)

    Chupp, Adam D; Battaglia, Loretta L; Schauber, Eric M; Sipes, Sedonia D

    2015-01-01

    Mutualistic relationships between plants and their pollinators have played a major role in the evolution of biodiversity. While the vulnerability of these relationships to environmental change is a major concern, studies often lack a framework for predicting impacts from emerging threats (e.g. biological invasions). The objective of this study was to determine the reliance of Platanthera ciliaris (orange-fringed orchid) on Papilio palamedes (Palamedes swallowtail butterfly) for pollination and the relative availability of alternative pollinators. Recent declines of P. palamedes larval host plants due to laurel wilt disease (LWD) could endanger P. ciliaris populations that rely heavily on this butterfly for pollination. We monitored pollinator visitation and fruit set and measured nectar spur lengths of P. ciliaris flowers and proboscis lengths of its floral visitors in Jackson County, MS, USA. Papilio palamedes was the primary visitor with minimal visitation by Phoebis sennae (cloudless sulfur butterfly). Lengths of P. ciliaris nectar spurs were similar to proboscis lengths of both pollinator species. Fruit set was moderate with access to pollinators (55 ± 10.8 %), yet failed (0 %) when pollinators were excluded. Visitation increased with inflorescence size, but there was no such pattern in fruit set, indicating that fruit set was not limited by pollinator visitation within the range of visitation rates we observed. Our results are supported by historical data that suggest P. palamedes and P. sennae are important pollinators of P. ciliaris. Although P. sennae may provide supplemental pollination service, this is likely constrained by habitat preferences that do not always overlap with those of P. cilaris. Observed declines of P. palamedes due to LWD could severely limit the reproductive success and persistence of P. ciliaris and similar orchid species populations. This empirical-based prediction is among the first to document exotic forest pests and pathogens as

  2. Non-Chemical Distant Cellular Interactions as a potential confounder of Cell Biology Experiments

    Directory of Open Access Journals (Sweden)

    Ashkan eFarhadi

    2014-10-01

    Full Text Available Distant cells can communicate with each other through a variety of methods. Two such methods involve electrical and/or chemical mechanisms. Non-chemical, distant cellular interactions may be another method of communication that cells can use to modify the behavior of other cells that are mechanically separated. Moreover, non-chemical, distant cellular interactions may explain some cases of confounding effects in Cell Biology experiments. In this article, we review non-chemical, distant cellular interactions studies to try to shed light on the mechanisms in this highly unconventional field of cell biology. Despite the existence of several theories that try to explain the mechanism of non-chemical, distant cellular interactions, this phenomenon is still speculative. Among candidate mechanisms, electromagnetic waves appear to have the most experimental support. In this brief article, we try to answer a few key questions that may further clarify this mechanism.

  3. Static magnetic fields: A summary of biological interactions, potential health effects, and exposure guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Tenforde, T.S.

    1992-05-01

    Interest in the mechanisms of interaction and the biological effects of static magnetic fields has increased significantly during the past two decades as a result of the growing number of applications of these fields in research, industry and medicine. A major stimulus for research on the bioeffects of static magnetic fields has been the effort to develop new technologies for energy production and storage that utilize intense magnetic fields (e.g., thermonuclear fusion reactors and superconducting magnet energy storage devices). Interest in the possible biological interactions and health effects of static magnetic fields has also been increased as a result of recent developments in magnetic levitation as a mode of public transportation. In addition, the rapid emergence of magnetic resonance imaging as a new clinical diagnostic procedure has, in recent years, provided a strong rationale for defining the possible biological effects of magnetic fields with high flux densities. In this review, the principal interaction mechanisms of static magnetic fields will be described, and a summary will be given of the present state of knowledge of the biological, environmental, and human health effects of these fields.

  4. Interaction of Ulocladium atrum, a Potential Biological Control Agent, with Botrytis cinerea and Grapevine Plantlets

    Directory of Open Access Journals (Sweden)

    Sébastien Ronseaux

    2013-09-01

    Full Text Available The effectiveness of biological control agent, Ulocladium atrum (isolates U13 and U16 in protecting Vitis vinifera L. cv. Chardonnay against gray mold disease caused by Botrytis cinerea, and simulation of the foliar defense responses was investigated. A degraded mycelium structure during cultural assay on potato dextrose agar revealed that U. atrum isolates U13 and U16 were both antagonistic to B. cinerea, mainly when isolates were inoculated two days before Botrytis. Under in vitro conditions, foliar application of U. atrum protected grapevine leaves against gray mold disease. An increase in chitinase activity was induced by the presence of U. atrum isolates indicating that the biological control agents triggered plant defense mechanisms. Moreover, U13 has the potential to colonize the grapevine plantlets and to improve their growth. The ability of U. atrum isolates to exhibit an antagonistic effect against B. cinerea in addition to their aptitude to induce plant resistance and to promote grapevine growth may explain a part of their biological activity. Hence, this study suggests that U. atrum provides a suitable biocontrol agent against gray mold in grapevines.

  5. Interaction of Ulocladium atrum, a Potential Biological Control Agent, with Botrytis cinerea and Grapevine Plantlets

    OpenAIRE

    Sébastien Ronseaux; Essaid Ait Barka; Christophe Clément

    2013-01-01

    The effectiveness of biological control agent, Ulocladium atrum (isolates U13 and U16) in protecting Vitis vinifera L. cv. Chardonnay against gray mold disease caused by Botrytis cinerea, and simulation of the foliar defense responses was investigated. A degraded mycelium structure during cultural assay on potato dextrose agar revealed that U. atrum isolates U13 and U16 were both antagonistic to B. cinerea, mainly when isolates were inoculated two days before Botrytis. Under in vitro conditio...

  6. Biological aspects of the potential interaction between androgen suppression and radiation therapy

    International Nuclear Information System (INIS)

    It is a basic axiom of radiotherapy that the radiation dose required for tumor eradication increases with increasing tumor volume. These Patterns of Care Studies and prospective studies using rebiopsy have shown that this holds true for prostate cancer as well. Despite our best endeavors with conventional dose, there remains a substantial element of local failure following radiotherapy, and this is T-stage related. Unlikely many other solid tumors, a convenient method of volume reduction exists for prostate carcinoma. Approximately 90% demonstrate shrinkage following androgen suppression, an effect that is more pronounced at the primary site than metastatic sites. Transrectal ultrasound studies have shown a median of 40% prostatic tumor volume reduction after 3-4 months of androgen suppression. With more protracted androgen suppression the shrinkage progresses and a small minority of patients may actually have a complete response determined pathologically. Animal models demonstrate clearly that the TCD50 of androgen dependent tumors may be decreased by prior androgen depression. This effect is most pronounced if radiation is deferred until the time of maximal tumor regression. The advantage is lost if the tumor is allowed to regrow in an androgen independent fashion to its original volume. It is not clear whether this benefit of neoadjuvant androgen suppression results solely from volume shrinkage. The potential for synergy exists as both radiation and androgen suppression have an element of apoptosis as a common pathway of cell death. Although apoptosis is certainly the major cause of cell death from androgen suppression its' contribution to radiation cell kill in prostatic adenocarcinomas is yet to be evaluated. If the two effects are additive and not synergistic, then sequence should be unimportant. Animal models, however, demonstrate that the TCD50 of androgen dependent tumors is not significantly reduced by adjuvant androgen suppression. Human data is still

  7. Potential bioactive Schiff base compounds: Synthesis, characterization, X-ray structures, biological screenings and interaction with Salmon sperm DNA

    Science.gov (United States)

    Sirajuddin, Muhammad; Uddin, Noor; Ali, Saqib; Tahir, Muhammad Nawaz

    2013-12-01

    Three Schiff base compounds ofN‧-substituted benzohydrazide and sulfonohydrazide derivatives: N‧-(2-hydroxy-3-methoxybenzylidene)-4-tert-butyl- benzohydrazide (1), N‧-(5-bromo-2-hydroxybenzylidene)-4-tert-butylbenzohydrazide (2) and N‧-(2-hydroxy-3-methoxybenzylidene)-4-methylbenzenesulfonohydrazide (3) were synthesized and characterized by elemental analysis, FT-IR, 1H, 13C NMR spectroscopy and single crystal analysis. The title compounds have been screened for their biological activities including, antibacterial, antifungal, antioxidant, cytotoxic, enzymatic activities as well as interaction with SS-DNA which showed remarkable activities in each area of research. The DNA binding of the compounds 1-3 with SS-DNA has been carried out with absorption spectroscopy, which reveals the binding propensity towards SS-DNA via intercalation mode of interaction. The intercalative mode of interaction is also supported by viscometric results. The synthesized compounds were also found to be effective against alkaline phosphatase enzyme. They also show significant to good antimicrobial activity against six bacterial and five fungal strains. The MIC (minimum inhibitory concentration) for antibacterial activity ranges from 1.95-500 μg/mL. Compounds 1-3 show cytotoxic activity comparable to the control. At higher conc. (100 μg/L) compound 3 shows 100% activity means that it has killed all brine shrimps. They were also found to be effective antioxidant of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and show almost comparable antioxidant activity to that of the standard and known antioxidant, ascorbic acid.

  8. Interactions between nematophagous fungi and consequences for their potential as biological agents for the control of potato cyst nematodes.

    Science.gov (United States)

    Jacobs, Helen; Gray, Simon N; Crump, David H

    2003-01-01

    The efficacies of three nematophagous fungi, Paecilomyces lilacinus, Plectosphaerella cucumerina and Pochonia chlamydosporia, for controlling potato cyst nematodes (PCN) as part of an Integrated Pest Management (IPM) regime were studied. The compatibility of the nematophagous fungi with commonly used chemical pesticides and their ability to compete with the soil fungi Rhizoctonia solani, Chaetomium globosum, Fusarium oxysporum, Penicillium bilaii and Trichoderma harzianum were tested in vitro. Paecilomyces lilacinus was the most successful competitor when the ability to grow and inhibit growth of an opposing colony at both 10 and 20 degrees C was considered. P. lilacinus also showed potential for control of the soil-borne fungal pathogen R. solani, releasing a diffusable substance in vitro which inhibited its growth and caused morphological abnormalities in its hyphae. Pochonia chlamydosporia was least susceptible to growth inhibition by other fungi at 20 degrees in vitro, but the isolate tested did not grow at 10 degrees. Plectosphaerella cucumerina was a poor saprophytic competitor. Radial growth of Paecilomyces lilacinus and Plectosphaerella cucumerina was slowed, but not prevented, when grown on potato dextrose agar incorporating the fungicides fenpiclonil and tolclofos-methyl, and was not inhibited by the addition of pencycuron or the nematicide oxamyl. Radial growth of Pochonia chlamydosporia was partially inhibited by all the chemical pesticides tested. The efficacy of Paecilomyces lilacinus as a control agent for R. solani was further investigated in situ. Treatment with P. lilacinus significantly reduced the symptoms of Rhizoctonia disease on potato stems in a pot trial. The effectiveness of P. lilacinus and P. cucumerina against PCN was also tested in situ. Three application methods were compared; incorporating the fungi into alginate pellets, Terra-Green inoculated with the fungi and applying conidia directly to the tubers. Both formulations containing P

  9. Review of Pasteuria penetrans: Biology, Ecology, and Biological Control Potential

    OpenAIRE

    Chen, Z. X.; Dickson, D. W.

    1998-01-01

    Pasteuria penetrans is a mycelial, endospore-forming, bacterial parasite that has shown great potential as a biological control agent of root-knot nematodes. Considerable progress has been made during the last 10 years in understanding its biology and importance as an agent capable of effectively suppressing root-knot nematodes in field soil. The objective of this review is to summarize the current knowledge of the biology, ecology, and biological control potential of P. penetrans and other P...

  10. A competing risks approach to "biologic" interaction

    DEFF Research Database (Denmark)

    Andersen, Per Kragh; Skrondal, Anders

    2015-01-01

    In epidemiology, the concepts of "biologic" and "statistical" interactions have been the subject of extensive debate. We present a new approach to biologic interaction based on Rothman's original (Am J Epidemiol, 104:587-592, 1976) discussion of sufficient causes. We do this in a probabilistic...

  11. Diatomic interaction potential theory applications

    CERN Document Server

    Goodisman, Jerry

    2013-01-01

    Diatomic Interaction Potential Theory, Volume 2: Applications discusses the variety of applicable theoretical material and approaches in the calculations for diatomic systems in their ground states. The volume covers the descriptions and illustrations of modern calculations. Chapter I discusses the calculation of the interaction potential for large and small values of the internuclear distance R (separated and united atom limits). Chapter II covers the methods used for intermediate values of R, which in principle means any values of R. The Hartree-Fock and configuration interaction schemes des

  12. Biological Implications of Gene-Environment Interaction

    Science.gov (United States)

    Rutter, Michael

    2008-01-01

    Gene-environment interaction (G x E) has been treated as both a statistical phenomenon and a biological reality. It is argued that, although there are important statistical issues that need to be considered, the focus has to be on the biological implications of G x E. Four reports of G x E deriving from the Dunedin longitudinal study are used as…

  13. Francisella tularensis - potential biological agent

    International Nuclear Information System (INIS)

    epidemic of glandular/oropharyngeal tularemia occurs in East part of the country (26 cases confirmed by serology only, subspecies not confirmed). F. tularensis could be used as a biological weapon in a number of ways. Release in a dense populated area would be expected to result in an abrupt onset of large numbers of acute, nonspecific febrile illness beginning after 3-5 days (incubation 1-14 days). An aerosol release would likely have the greatest adverse medical and public health consequences. Airborne F. tularensis would be expected to principally cause pleuropneumonitis, might contaminate the eye (ocular tularaemia); penetrate broken skin (ulceroglandular or glandular disease); or cause oropharyngeal disease with cervical lymphadenitis. Stockpiling effective antibiotics to treat infected people, coordinating a nation-wide program, sharing of information, education for health professionals (prevention, diagnosis, treatment), the public and the media are essential needs for prevention and control of tularemia, occurred naturally or by possible bio attack by F.tularensis.(author)

  14. Interaction of electromagnetic fields and biological tissues

    Science.gov (United States)

    Darshan Shrivastava, Bhakt; Barde, Ravindra; Mishra, Ashutosh; Phadke, S.

    2014-09-01

    This paper deals with the electromagnetic field interact in biological tissues. It is actually one of the important challenges for the electromagnetic field for the recent years. The experimental techniques are use in Broad-band Dielectric Measurement (BDM) with LCR meters. The authors used Bones and scales of Fish taken from Narmada River (Rajghat Dist. Barwani) as biological tissues. Experimental work carried out done in inter-university consortium (IUC) Indore. The major difficulties that appear are related to the material properties, to the effect of the electromagnetic problem and to the thermal model of the biological tissues.

  15. Higgs Potential from Derivative Interactions

    CERN Document Server

    Quadri, A

    2016-01-01

    A formulation of the linear $\\sigma$ model with derivative interactions is studied. The theory is on-shell equivalent to the model with a quartic Higgs potential. The mass of the scalar mode only appears in the quadratic part and not in the interaction vertices, unlike in the ordinary formulation of the theory. Renormalization of the model is discussed. A natural non power-counting renormalizable extension of the theory is presented. The model is physically equivalent to the inclusion of a dimension six effective operator $\\partial_\\mu (\\Phi^\\dagger \\Phi) \\partial^\\mu (\\Phi^\\dagger \\Phi)$. The resulting UV divergences are arranged in a perturbation series around the power-counting renormalizable theory. UV completion of the non-power-counting renormalizable model through a symmetric deformation of the propagator of the massive physical scalar is addressed.

  16. Randomness and Criticality in Biological Interactions

    OpenAIRE

    Grilli, Jacopo

    2015-01-01

    In this thesis we study from a physics perspective two problems related to biological interactions. In the first part of this thesis we consider ecological interactions, that shape ecosystems and determine their fate, and their relation with stability of ecosystems. Using random matrix theory we are able to identify the key aspect, the order parameters, determining the stability of large ecosystems. We then consider the problem of determining the persistence of a population living in a random...

  17. Gold Nanoparticle-Biological Molecule Interactions and Catalysis

    Directory of Open Access Journals (Sweden)

    Jonathan G. Heddle

    2013-09-01

    Full Text Available This review gives a brief summary of the field of gold nanoparticle interactions with biological molecules, particularly those with possible catalytic relevance. Gold nanoparticles are well known as catalysts in organic chemistry but much is unknown regarding their potential as catalysts of reactions involving biological molecules such as protein and nucleic acids. Biological molecules may be the substrate for catalysis or, if they are the ligand coating the gold particle, may be the catalyst itself. In other cases biological molecules may form a template upon which gold nanoparticles can be precisely arrayed. As relatively little is currently known about the catalytic capabilities of gold nanoparticles in this area, this review will consider templating in general (including, but not restricted to, those which result in structures having potential as catalysts before going on to consider firstly catalysis by the gold nanoparticle itself followed by catalysis by ligands attached to gold nanoparticles, all considered with a focus on biological molecules.

  18. Laser interaction with biological material mathematical modeling

    CERN Document Server

    Kulikov, Kirill

    2014-01-01

    This book covers the principles of laser interaction with biological cells and tissues of varying degrees of organization. The problems of biomedical diagnostics are considered. Scattering of laser irradiation of blood cells is modeled for biological structures (dermis, epidermis, vascular plexus). An analytic theory is provided which is based on solving the wave equation for the electromagnetic field. It allows the accurate analysis of interference effects arising from the partial superposition of scattered waves. Treated topics of mathematical modeling are: optical characterization of biological tissue with large-scale and small-scale inhomogeneities in the layers, heating blood vessel under laser irradiation incident on the outer surface of the skin and thermo-chemical denaturation of biological structures at the example of human skin.

  19. Integrating interactive computational modeling in biology curricula.

    Directory of Open Access Journals (Sweden)

    Tomáš Helikar

    2015-03-01

    Full Text Available While the use of computer tools to simulate complex processes such as computer circuits is normal practice in fields like engineering, the majority of life sciences/biological sciences courses continue to rely on the traditional textbook and memorization approach. To address this issue, we explored the use of the Cell Collective platform as a novel, interactive, and evolving pedagogical tool to foster student engagement, creativity, and higher-level thinking. Cell Collective is a Web-based platform used to create and simulate dynamical models of various biological processes. Students can create models of cells, diseases, or pathways themselves or explore existing models. This technology was implemented in both undergraduate and graduate courses as a pilot study to determine the feasibility of such software at the university level. First, a new (In Silico Biology class was developed to enable students to learn biology by "building and breaking it" via computer models and their simulations. This class and technology also provide a non-intimidating way to incorporate mathematical and computational concepts into a class with students who have a limited mathematical background. Second, we used the technology to mediate the use of simulations and modeling modules as a learning tool for traditional biological concepts, such as T cell differentiation or cell cycle regulation, in existing biology courses. Results of this pilot application suggest that there is promise in the use of computational modeling and software tools such as Cell Collective to provide new teaching methods in biology and contribute to the implementation of the "Vision and Change" call to action in undergraduate biology education by providing a hands-on approach to biology.

  20. Institute for Multiscale Modeling of Biological Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Paulaitis, Michael E; Garcia-Moreno, Bertrand; Lenhoff, Abraham

    2009-12-26

    The Institute for Multiscale Modeling of Biological Interactions (IMMBI) has two primary goals: Foster interdisciplinary collaborations among faculty and their research laboratories that will lead to novel applications of multiscale simulation and modeling methods in the biological sciences and engineering; and Building on the unique biophysical/biology-based engineering foundations of the participating faculty, train scientists and engineers to apply computational methods that collectively span multiple time and length scales of biological organization. The success of IMMBI will be defined by the following: Size and quality of the applicant pool for pre-doctoral and post-doctoral fellows; Academic performance; Quality of the pre-doctoral and post-doctoral research; Impact of the research broadly and to the DOE (ASCR program) mission; Distinction of the next career step for pre-doctoral and post-doctoral fellows; and Faculty collaborations that result from IMMBI activities. Specific details about accomplishments during the three years of DOE support for IMMBI have been documented in Annual Progress Reports (April 2005, June 2006, and March 2007) and a Report for a National Academy of Sciences Review (October 2005) that were submitted to DOE on the dates indicated. An overview of these accomplishments is provided.

  1. Potential biological activity of acacia honey.

    Science.gov (United States)

    Muhammad, Aliyu; Odunola, Oyeronke A; Ibrahim, Mohammed A; Sallau, Abdullahi B; Erukainure, Ochuko L; Aimola, Idown A; Malami, Ibrahim

    2016-01-01

    Recent advances in functional foods-based research have increasingly become an area of major interest because it affects human health and activities. Functional foods are classes of foods with health promoting and disease preventing properties in addition to multiple nutritional values and of such type is honey. Acacia honey is a type of honey produced by bees (Apis mellifera) fed on Acacia flowers, hence the name. This review focuses on the potential biological activities of Acacia honey which includes quality, antioxidant, immuno-modulatory, antiproliferative and neurological properties at in vitro and in vivo levels. Based on our review, Acacia honey used from various researches is of high purity, contains some bioactive compounds ranging from vitamins, phenolics, flavonoids and fatty acids. It's highly nutritional with strong antioxidant and immuno-modulatory potentials which may therefore be considered a potential candidate for both cancer prevention and treatment. Neurologically, it may be considered as a viable therapeutic agent in the management of Alzheimer's disease. PMID:26709666

  2. Neutron interactions with biological tissue. Final report

    International Nuclear Information System (INIS)

    This program was aimed at creating a quantitative physical description, at the micrometer and nanometer levels, of the physical interactions of neutrons with tissue through the ejected secondary charged particles. The authors used theoretical calculations whose input includes neutron cross section data; range, stopping power, ion yield, and straggling information; and geometrical properties. Outputs are initial and slowing-down spectra of charged particles, kerma factors, average values of quality factors, microdosimetric spectra, and integral microdosimetric parameters such as bar yF, bar yD, y*. Since it has become apparent that nanometer site sizes are also relevant to radiobiological effects, the calculations of event size spectra and their parameters were extended to these smaller diameters. This information is basic to radiological physics, radiation biology, radiation protection of workers, and standards for neutron dose measurement

  3. Developing a general interaction potential for hydrophobic and hydrophilic interactions.

    Science.gov (United States)

    Donaldson, Stephen H; Røyne, Anja; Kristiansen, Kai; Rapp, Michael V; Das, Saurabh; Gebbie, Matthew A; Lee, Dong Woog; Stock, Philipp; Valtiner, Markus; Israelachvili, Jacob

    2015-02-24

    We review direct force measurements on a broad class of hydrophobic and hydrophilic surfaces. These measurements have enabled the development of a general interaction potential per unit area, W(D) = -2γ(i)Hy exp(-D/D(H)) in terms of a nondimensional Hydra parameter, Hy, that applies to both hydrophobic and hydrophilic interactions between extended surfaces. This potential allows one to quantitatively account for additional attractions and repulsions not included in the well-known combination of electrostatic double layer and van der Waals theories, the so-called Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. The interaction energy is exponentially decaying with decay length D(H) ≈ 0.3-2 nm for both hydrophobic and hydrophilic interactions, with the exact value of D(H) depending on the precise system and conditions. The pre-exponential factor depends on the interfacial tension, γ(i), of the interacting surfaces and Hy. For Hy > 0, the interaction potential describes interactions between partially hydrophobic surfaces, with the maximum hydrophobic interaction (i.e., two fully hydrophobic surfaces) corresponding to Hy = 1. Hydrophobic interactions between hydrophobic monolayer surfaces measured with the surface forces apparatus (SFA) are shown to be well described by the proposed interaction potential. The potential becomes repulsive for Hy < 0, corresponding to partially hydrophilic (hydrated) interfaces. Hydrated surfaces such as mica, silica, and lipid bilayers are discussed and reviewed in the context of the values of Hy appropriate for each system.

  4. Discrete Time Markovian Agents Interacting Through a Potential

    CERN Document Server

    Budhiraja, Amarjit; Rubenthaler, Sylvain

    2011-01-01

    A discrete time stochastic model for a multiagent system given in terms of a large collection of interacting Markov chains is studied. The evolution of the interacting particles is described through a time inhomogeneous transition probability kernel that depends on the 'gradient' of the potential field. The particles, in turn, dynamically modify the potential field through their cumulative input. Interacting Markov processes of the above form have been suggested as models for active biological transport in response to external stimulus such as a chemical gradient. One of the basic mathematical challenges is to develop a general theory of stability for such interacting Markovian systems and for the corresponding nonlinear Markov processes that arise in the large agent limit. Such a theory would be key to a mathematical understanding of the interactive structure formation that results from the complex feedback between the agents and the potential field. It will also be a crucial ingredient in developing simulat...

  5. Potential interactions between alternative therapies and warfarin.

    Science.gov (United States)

    Heck, A M; DeWitt, B A; Lukes, A L

    2000-07-01

    Potential and documented interactions between alternative therapy agents and warfarin are discussed. An estimated one third of adults in the United States use alternative therapies, including herbs. A major safety concern is potential interactions of alternative medicine products with prescription medications. This issue is especially important with respect to drugs with narrow therapeutic indexes, such as warfarin. Herbal products that may potentially increase the risk of bleeding or potentiate the effects of warfarin therapy include angelica root, arnica flower, anise, asafoetida, bogbean, borage seed oil, bromelain, capsicum, celery, chamomile, clove, fenugreek, feverfew, garlic, ginger ginkgo, horse chestnut, licorice root, lovage root, meadowsweet, onion, parsley, passionflower herb, poplar, quassia, red clover, rue, sweet clover, turmeric, and willow bark. Products that have been associated with documented reports of potential interactions with warfarin include coenzyme Q10, danshen, devil's claw, dong quai, ginseng, green tea, papain, and vitamin E. Interpretation of the available information on herb-warfarin interactions is difficult because nearly all of it is based on in vitro data, animal studies, or individual case reports. More study is needed to confirm and assess the clinical significance of these potential interactions. There is evidence that a wide range of alternative therapy products have the potential to interact with warfarin. Pharmacists and other health care professionals should question all patients about use of alternative therapies and report documented interactions to FDA's MedWatch program. PMID:10902065

  6. Potential interactions between alternative therapies and warfarin.

    Science.gov (United States)

    Heck, A M; DeWitt, B A; Lukes, A L

    2000-07-01

    Potential and documented interactions between alternative therapy agents and warfarin are discussed. An estimated one third of adults in the United States use alternative therapies, including herbs. A major safety concern is potential interactions of alternative medicine products with prescription medications. This issue is especially important with respect to drugs with narrow therapeutic indexes, such as warfarin. Herbal products that may potentially increase the risk of bleeding or potentiate the effects of warfarin therapy include angelica root, arnica flower, anise, asafoetida, bogbean, borage seed oil, bromelain, capsicum, celery, chamomile, clove, fenugreek, feverfew, garlic, ginger ginkgo, horse chestnut, licorice root, lovage root, meadowsweet, onion, parsley, passionflower herb, poplar, quassia, red clover, rue, sweet clover, turmeric, and willow bark. Products that have been associated with documented reports of potential interactions with warfarin include coenzyme Q10, danshen, devil's claw, dong quai, ginseng, green tea, papain, and vitamin E. Interpretation of the available information on herb-warfarin interactions is difficult because nearly all of it is based on in vitro data, animal studies, or individual case reports. More study is needed to confirm and assess the clinical significance of these potential interactions. There is evidence that a wide range of alternative therapy products have the potential to interact with warfarin. Pharmacists and other health care professionals should question all patients about use of alternative therapies and report documented interactions to FDA's MedWatch program.

  7. A new model of the microwave interaction with biological systems

    International Nuclear Information System (INIS)

    The interaction of 30-300 GHz electromagnetic field with biological media is studied . The refraction index and the extinction, reflection and transmission coefficients were shown to depend on concentration of coherent photons created by the biological objects and their dependence was studied on the biological medium excitation level, the non-linear character of this dependence being established. (authors)

  8. Coherent EM field interaction with biological media

    International Nuclear Information System (INIS)

    The action of the mm-waves upon medical-biological objects is studied. A generalized theory of induced Bose condensation of phonons and photons under the action of mm-waves in biological systems is worked out, using the quantum theory of fluctuations and attenuation. (author)

  9. Computational Structural Biology of Macromolecular Interactions

    NARCIS (Netherlands)

    Garcia Lopes Maia Rodrigues, J.

    2014-01-01

    The living cell is a formidable entity kept intact and functioning by a network of interactions carried out by protein molecules. As such, understanding this network, the interactome, is key to understand the cell itself. To dissect the fundamental properties of protein interactions, researchers use

  10. A new interaction potential for swarming models

    Science.gov (United States)

    Carrillo, J. A.; Martin, S.; Panferov, V.

    2013-10-01

    We consider a self-propelled particle system which has been used to describe certain types of collective motion of animals, such as fish schools and bird flocks. Interactions between particles are specified by means of a pairwise potential, repulsive at short ranges and attractive at longer ranges. The exponentially decaying Morse potential is a typical choice, and is known to reproduce certain types of collective motion observed in nature, particularly aligned flocks and rotating mills. We introduce a class of interaction potentials, that we call Quasi-Morse, for which flock and rotating mills states are also observed numerically, however in that case the corresponding macroscopic equations allow for explicit solutions in terms of special functions, with coefficients that can be obtained numerically without solving the particle evolution. We compare the obtained solutions with long-time dynamics of the particle systems and find a close agreement for several types of flock and mill solutions.

  11. A new interaction potential for swarming models

    CERN Document Server

    Carrillo, J A; Panferov, V

    2012-01-01

    We consider a self-propelled particle system which has been used to describe certain types of collective motion of animals, such as fish schools and bird flocks. Interactions between particles are specified by means of a pairwise potential, repulsive at short ranges and attractive at longer ranges. The exponentially decaying Morse potential is a typical choice, and is known to reproduce certain types of collective motion observed in nature, particularly aligned flocks and rotating mills. We introduce a class of interaction potentials, that we call Quasi-Morse, for which flock and rotating mills states are also observed numerically, however in that case the corresponding macroscopic equations allow for explicit solutions in terms of special functions, with coefficients that can be obtained numerically without solving the particle evolution. We compare thus obtained solutions with long-time dynamics of the particle systems and find a close agreement for several types of flock and mill solutions.

  12. Interactive analysis of systems biology molecular expression data

    OpenAIRE

    Prabhakar Sunil; Salt David E; Kane Michael D; Stephenson Alan; Ouyang Qi; Zhang Mingwu; Burgner John; Buck Charles; Zhang Xiang

    2008-01-01

    Abstract Background Systems biology aims to understand biological systems on a comprehensive scale, such that the components that make up the whole are connected to one another and work through dependent interactions. Molecular correlations and comparative studies of molecular expression are crucial to establishing interdependent connections in systems biology. The existing software packages provide limited data mining capability. The user must first generate visualization data with a preferr...

  13. Statistical systems with nonintegrable interaction potentials

    Science.gov (United States)

    Yukalov, V. I.

    2016-07-01

    Statistical systems composed of atoms interacting with each other trough nonintegrable interaction potentials are considered. Examples of these potentials are hard-core potentials and long-range potentials, for instance, the Lennard-Jones and dipolar potentials. The treatment of such potentials is known to confront several problems, e.g., the impossibility of using the standard mean-field approximations, such as Hartree and Hartree-Fock approximations, the impossibility of directly introducing coherent states, the difficulty in breaking the global gauge symmetry, which is required for describing Bose-Einstein condensed and superfluid systems, the absence of a correctly defined Fourier transform, which hampers the description of uniform matter as well as the use of local-density approximation for nonuniform systems. A novel iterative procedure for describing such systems is developed, starting from a correlated mean-field approximation, allowing for a systematic derivation of higher orders, and meeting no problems listed above. The procedure is applicable to arbitrary systems, whether equilibrium or nonequilibrium. The specification for equilibrium systems is presented. The method of extrapolating the expressions for observable quantities from weak coupling to strong coupling is described.

  14. Interactive analysis of systems biology molecular expression data

    Directory of Open Access Journals (Sweden)

    Prabhakar Sunil

    2008-02-01

    Full Text Available Abstract Background Systems biology aims to understand biological systems on a comprehensive scale, such that the components that make up the whole are connected to one another and work through dependent interactions. Molecular correlations and comparative studies of molecular expression are crucial to establishing interdependent connections in systems biology. The existing software packages provide limited data mining capability. The user must first generate visualization data with a preferred data mining algorithm and then upload the resulting data into the visualization package for graphic visualization of molecular relations. Results Presented is a novel interactive visual data mining application, SysNet that provides an interactive environment for the analysis of high data volume molecular expression information of most any type from biological systems. It integrates interactive graphic visualization and statistical data mining into a single package. SysNet interactively presents intermolecular correlation information with circular and heatmap layouts. It is also applicable to comparative analysis of molecular expression data, such as time course data. Conclusion The SysNet program has been utilized to analyze elemental profile changes in response to an increasing concentration of iron (Fe in growth media (an ionomics dataset. This study case demonstrates that the SysNet software is an effective platform for interactive analysis of molecular expression information in systems biology.

  15. The Potential Impact of Droplet Microfluidics in Biology

    OpenAIRE

    Schneider, Thomas; Kreutz, Jason; Chiu, Daniel T.

    2013-01-01

    Droplet microfluidics, which involves micrometer-sized emulsion droplets on a microfabricated platform, is an active research endeavor that evolved out of the larger field of microfluidics. Recently, this subfield of microfluidics has started to attract greater interest because researchers have been able to demonstrate applications of droplets as miniaturized laboratories for biological measurements. This perspective explores the recent developments and the potential future biological applica...

  16. PathSys: integrating molecular interaction graphs for systems biology

    Directory of Open Access Journals (Sweden)

    Raval Alpan

    2006-02-01

    Full Text Available Abstract Background The goal of information integration in systems biology is to combine information from a number of databases and data sets, which are obtained from both high and low throughput experiments, under one data management scheme such that the cumulative information provides greater biological insight than is possible with individual information sources considered separately. Results Here we present PathSys, a graph-based system for creating a combined database of networks of interaction for generating integrated view of biological mechanisms. We used PathSys to integrate over 14 curated and publicly contributed data sources for the budding yeast (S. cerevisiae and Gene Ontology. A number of exploratory questions were formulated as a combination of relational and graph-based queries to the integrated database. Thus, PathSys is a general-purpose, scalable, graph-data warehouse of biological information, complete with a graph manipulation and a query language, a storage mechanism and a generic data-importing mechanism through schema-mapping. Conclusion Results from several test studies demonstrate the effectiveness of the approach in retrieving biologically interesting relations between genes and proteins, the networks connecting them, and of the utility of PathSys as a scalable graph-based warehouse for interaction-network integration and a hypothesis generator system. The PathSys's client software, named BiologicalNetworks, developed for navigation and analyses of molecular networks, is available as a Java Web Start application at http://brak.sdsc.edu/pub/BiologicalNetworks.

  17. PRESENTATION POTENTIAL USING IN PEDAGOGICAL INTERACTION PROCESS

    Directory of Open Access Journals (Sweden)

    Olga V. Ershova

    2016-01-01

    Full Text Available The given article is aimed at considering multimedia presentation potential and its influence on strengthening classroom teacher-student interaction. In the article the importance of using this kind of activity in the study process is pointed in connection with educational state policy on the one hand. On the other hand, gained students’ skills as a final result of work with presentations met employers’ demand for both parent and world labour-markets and bring competitive benefit to the candidates. Scientific novelty and results. Multimedia presentation is considered as a specific complex of classroom activities. The students are oriented on the self analysis and presentation assessment. It is shown that well-organized process of peer students’ assessment allows to simultaneously helping in solving the didactic and methodical problems. To this purpose the system of assessment criteria should be developed. It has to be clear for students for making assessment feasible and time-saving. The example of a possible variant of criteria system is described; quality of the presentations prepared by students can be defined based on such system criteria. The author also analyzed software products of the three main platforms (Windows, Linux, MacOs which have different tools and allow to follow users’ needs for creating presentations. In the article there is a comparative table of the two most popular software development: the program Microsoft PowerPoint and the web-service Prezi for realizing the relevance of their use in the study process. Practical significance of the present article concludes in author’s suggestions of some recommendations for presentation potential use as a tool of improving pedagogical interaction process with contemporary students. 

  18. Chemical and biological rhizosphere interactions in low zinc soils

    NARCIS (Netherlands)

    Duffner, A.

    2014-01-01

    Abstract of the PhD thesis entitled “Chemical and biological rhizosphere interactions in low zinc soils” by Andreas Duffner Soil provides ecosystem services critical for life. The availability of micronutrients, such as zinc (Zn), in soils is an essenti

  19. The potential for biological structure determination with pulsed neutrons

    International Nuclear Information System (INIS)

    The potential of pulsed neutron diffraction in structural determination of biological materials is discussed. The problems and potential solutions in this area are outlined, with reference to both current and future sources and instrumentation. The importance of developing instrumentation on pulsed sources in emphasized, with reference to the likelihood of future expansion in this area. The possibilities and limitations of single crystal, fiber and powder diffraction in this area are assessed

  20. The potential for biological structure determination with pulsed neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, C.C. [CLRC Rutherford Appleton Laboratory, Chilton Didcot Oxon (United Kingdom)

    1994-12-31

    The potential of pulsed neutron diffraction in structural determination of biological materials is discussed. The problems and potential solutions in this area are outlined, with reference to both current and future sources and instrumentation. The importance of developing instrumentation on pulsed sources in emphasized, with reference to the likelihood of future expansion in this area. The possibilities and limitations of single crystal, fiber and powder diffraction in this area are assessed.

  1. Macroscopic Quantum-Type Potentials in Theoretical Systems Biology

    Directory of Open Access Journals (Sweden)

    Laurent Nottale

    2013-12-01

    Full Text Available We review in this paper the use of the theory of scale relativity and fractal space-time as a tool particularly well adapted to the possible development of a future genuine systems theoretical biology. We emphasize in particular the concept of quantum-type potentials, since, in many situations, the effect of the fractality of space—or of the underlying medium—can be reduced to the addition of such a potential energy to the classical equations of motion. Various equivalent representations—geodesic, quantum-like, fluid mechanical, stochastic—of these equations are given, as well as several forms of generalized quantum potentials. Examples of their possible intervention in high critical temperature superconductivity and in turbulence are also described, since some biological processes may be similar in some aspects to these physical phenomena. These potential extra energy contributions could have emerged in biology from the very fractal nature of the medium, or from an evolutive advantage, since they involve spontaneous properties of self-organization, morphogenesis, structuration and multi-scale integration. Finally, some examples of applications of the theory to actual biological-like processes and functions are also provided.

  2. Chemical Force Microscopy of Chemical and Biological Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Noy, A

    2006-01-02

    Interactions between chemical functionalities define outcomes of the vast majority of important events in chemistry, biology and materials science. Chemical Force Microscopy (CFM)--a technique that uses direct chemical functionalization of AFM probes with specific functionalities--allows researchers to investigate these important interactions directly. We review the basic principles of CFM, some examples of its application, and theoretical models that provide the basis for understanding the experimental results. We also emphasize application of modern kinetic theory of non-covalent interactions strength to the analysis of CFM data.

  3. Biologically erodable microspheres as potential oral drug delivery systems

    Science.gov (United States)

    Mathiowitz, Edith; Jacob, Jules S.; Jong, Yong S.; Carino, Gerardo P.; Chickering, Donald E.; Chaturvedi, Pravin; Santos, Camilla A.; Vijayaraghavan, Kavita; Montgomery, Sean; Bassett, Michael; Morrell, Craig

    1997-03-01

    Biologically adhesive delivery systems offer important advantages1-5 over conventional drug delivery systems6. Here we show that engineered polymer microspheres made of biologically erodable polymers, which display strong adhesive interactions with gastrointestinal mucus and cellular linings, can traverse both the mucosal absorptive epithelium and the follicle-associated epithelium covering the lymphoid tissue of Peyer's patches. The polymers maintain contact with intestinal epithelium for extended periods of time and actually penetrate it, through and between cells. Thus, once loaded with compounds of pharmacological interest, the microspheres could be developed as delivery systems to transfer biologically active molecules to the circulation. We show that these microspheres increase the absorption of three model substances of widely different molecular size: dicumarol, insulin and plasmid DNA.

  4. Interaction mechanisms and biological effects of static magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Tenforde, T.S.

    1994-06-01

    Mechanisms through which static magnetic fields interact with living systems are described and illustrated by selected experimental observations. These mechanisms include electrodynamic interactions with moving, ionic charges (blood flow and nerve impulse conduction), magnetomechanical interactions (orientation and translation of molecules structures and magnetic particles), and interactions with electronic spin states in charge transfer reactions (photo-induced electron transfer in photosynthesis). A general summary is also presented of the biological effects of static magnetic fields. There is convincing experimental evidence for magnetoreception mechanisms in several classes of lower organisms, including bacteria and marine organisms. However, in more highly evolved species of animals, there is no evidence that the interactions of static magnetic fields with flux densities up to 2 Tesla (1 Tesla [T] = 10{sup 4} Gauss) produce either behavioral or physiolocical alterations. These results, based on controlled studies with laboratory animals, are consistent with the outcome of recent epidemiological surveys on human populations exposed occupationally to static magnetic fields.

  5. Synthetic Biology and Human Health: Potential Applications for Spaceflight

    Science.gov (United States)

    Karouia, Fathi; Carr, Christopher; Cai, Yizhi; Chen, Y.; Grenon, Marlene; Larios-Sanz, Maia; Jones, Jeffrey A.; Santos, Orlando

    2011-01-01

    Human space travelers experience a unique environment that affects homeostasis and physiologic adaptation. Spaceflight-related changes have been reported in the musculo-skeletal, cardiovascular, neurovestibular, endocrine, and immune systems. The spacecraft environment further subjects the traveler to noise and gravitational forces, as well as airborne chemical, microbiological contaminants, and radiation exposure. As humans prepare for longer duration missions effective countermeasures must be developed, verified, and implemented to ensure mission success. Over the past ten years, synthetic biology has opened new avenues for research and development in areas such as biological control, biomaterials, sustainable energy production, bioremediation, and biomedical therapies. The latter in particular is of great interest to the implementation of long-duration human spaceflight capabilities. This article discusses the effects of spaceflight on humans, and reviews current capabilities and potential needs associated with the health of the astronauts where synthetic biology could play an important role in the pursuit of space exploration.

  6. Biologically controlled minerals as potential indicators of life

    Science.gov (United States)

    Schwartz, D. E.; Mancinelli, R. L.; Kaneshiro, E.

    1991-01-01

    Minerals can be produced and deposited either by abiotic or biologic means. Regardless of their origin, mineral crystals reflect the environment conditions (e.g., temperature, pressure, chemical composition, and redox potential) present during crystal formation. Biologically-produced mineral crystals are grown or reworked under the control of their host organism and reflect an environment different from the abiotic environment. In addition, minerals of either biologic or abiotic origin have great longevities. For these reasons, biologically produced minerals have been proposed as biomarkers. Biomarkers are key morphological, chemical, and isotopic signatures of living systems that can be used to determine if life processes have occurred. Studies of biologically controlled minerals produced by the protist, Paramecium tetraurelia, were initiated since techniques have already been developed to culture them and isolate their crystalline material, and methods are already in place to analyze this material. Two direct crystalline phases were identified. One phase, whose chemical composition is high in Mg, was identified as struvite. The second phase, whose chemical composition is high in Ca, has not been previously found occurring naturally and may be considered a newly discovered material. Analyses are underway to determine the characteristics of these minerals in order to compare them with characteristics of these minerals in order to compare them with characteristics of minerals formed abiotically, but with the same chemical composition.

  7. Potential of Biological Agents in Decontamination of Agricultural Soil

    OpenAIRE

    Javaid, Muhammad Kashif; Ashiq, Mehrban; Tahir, Muhammad

    2016-01-01

    Pesticides are widely used for the control of weeds, diseases, and pests of cultivated plants all over the world, mainly since the period after the Second World War. The use of pesticides is very extensive to control harm of pests all over the globe. Persistent nature of most of the synthetic pesticides causes serious environmental concerns. Decontamination of these hazardous chemicals is very essential. This review paper elaborates the potential of various biological agents in decontaminatio...

  8. Chemical and biological rhizosphere interactions in low zinc soils

    OpenAIRE

    Duffner, A.

    2014-01-01

    Abstract of the PhD thesis entitled “Chemical and biological rhizosphere interactions in low zinc soils” by Andreas Duffner Soil provides ecosystem services critical for life. The availability of micronutrients, such as zinc (Zn), in soils is an essential factor for normal healthy growth and reproduction of plants. Zinc deficiency is, however, a global problem in crop production due to low Zn bioavailability in soils to plants. The bioavailable Zn fraction in soils is controlled ...

  9. Discerning mechanistically rewired biological pathways by cumulative interaction heterogeneity statistics.

    Science.gov (United States)

    Cotton, Travis B; Nguyen, Hien H; Said, Joseph I; Ouyang, Zhengyu; Zhang, Jinfa; Song, Mingzhou

    2015-01-01

    Changes in response of a biological pathway could be a consequence of either pathway rewiring, changed input, or a combination of both. Most pathway analysis methods are not designed for mechanistic rewiring such as regulatory element variations. This limits our understanding of biological pathway evolution. Here we present a Q-method to discern whether changed pathway response is caused by mechanistic rewiring of pathways due to evolution. The main innovation is a cumulative pathway interaction heterogeneity statistic accounting for rewiring-specific effects on the rate of change of each molecular variable across conditions. The Q-method remarkably outperformed differential-correlation based approaches on data from diverse biological processes. Strikingly, it also worked well in differentiating rewired chaotic systems, whose dynamics are notoriously difficult to predict. Applying the Q-method on transcriptome data of four yeasts, we show that pathway interaction heterogeneity for known metabolic and signaling pathways is indeed a predictor of interspecies genetic rewiring due to unbalanced TATA box-containing genes among the yeasts. The demonstrated effectiveness of the Q-method paves the way to understanding network evolution at the resolution of functional biological pathways. PMID:25921728

  10. Elucidating the Potential Biological Impact of Cellulose Nanocrystals

    Directory of Open Access Journals (Sweden)

    Sandra Camarero-Espinosa

    2016-07-01

    Full Text Available Cellulose nanocrystals exhibit an interesting combination of mechanical properties and physical characteristics, which make them potentially useful for a wide range of consumer applications. However, as the usage of these bio-based nanofibers increases, a greater understanding of human exposure addressing their potential health issues should be gained. The aim of this perspective is to highlight how knowledge obtained from studying the biological impact of other nanomaterials can provide a basis for future research strategies to deduce the possible human health risks posed by cellulose nanocrystals.

  11. Finding optimal interaction interface alignments between biological complexes

    KAUST Repository

    Cui, Xuefeng

    2015-06-13

    Motivation: Biological molecules perform their functions through interactions with other molecules. Structure alignment of interaction interfaces between biological complexes is an indispensable step in detecting their structural similarities, which are keys to understanding their evolutionary histories and functions. Although various structure alignment methods have been developed to successfully access the similarities of protein structures or certain types of interaction interfaces, existing alignment tools cannot directly align arbitrary types of interfaces formed by protein, DNA or RNA molecules. Specifically, they require a \\'blackbox preprocessing\\' to standardize interface types and chain identifiers. Yet their performance is limited and sometimes unsatisfactory. Results: Here we introduce a novel method, PROSTA-inter, that automatically determines and aligns interaction interfaces between two arbitrary types of complex structures. Our method uses sequentially remote fragments to search for the optimal superimposition. The optimal residue matching problem is then formulated as a maximum weighted bipartite matching problem to detect the optimal sequence order-independent alignment. Benchmark evaluation on all non-redundant protein-DNA complexes in PDB shows significant performance improvement of our method over TM-align and iAlign (with the \\'blackbox preprocessing\\'). Two case studies where our method discovers, for the first time, structural similarities between two pairs of functionally related protein-DNA complexes are presented. We further demonstrate the power of our method on detecting structural similarities between a protein-protein complex and a protein-RNA complex, which is biologically known as a protein-RNA mimicry case. © The Author 2015. Published by Oxford University Press.

  12. Long-range resonant interactions in biological systems

    CERN Document Server

    Preto, Jordane

    2012-01-01

    The issue of retarded long-range resonant interactions between two molecules with oscillating dipole moments is reinvestigated within the framework of classical electrodynamics. By taking advantage of a theorem in complex analysis, we present a simple method to work out the frequencies of the normal modes, which are then used to estimate the interaction potential. The main results thus found are in perfect agreement with several outcomes obtained from quantum computations. Moreover, when applied to a biophysical context, our findings shed new light on Fr\\"ohlich's theory of selective long-range interactions between biomolecules. In particular, at variance with a long-standing belief, we show that sizable resonant long-range interactions may exist only if the interacting system is out of thermal equilibrium.

  13. Computing paths and cycles in biological interaction graphs

    Directory of Open Access Journals (Sweden)

    von Kamp Axel

    2009-06-01

    Full Text Available Abstract Background Interaction graphs (signed directed graphs provide an important qualitative modeling approach for Systems Biology. They enable the analysis of causal relationships in cellular networks and can even be useful for predicting qualitative aspects of systems dynamics. Fundamental issues in the analysis of interaction graphs are the enumeration of paths and cycles (feedback loops and the calculation of shortest positive/negative paths. These computational problems have been discussed only to a minor extent in the context of Systems Biology and in particular the shortest signed paths problem requires algorithmic developments. Results We first review algorithms for the enumeration of paths and cycles and show that these algorithms are superior to a recently proposed enumeration approach based on elementary-modes computation. The main part of this work deals with the computation of shortest positive/negative paths, an NP-complete problem for which only very few algorithms are described in the literature. We propose extensions and several new algorithm variants for computing either exact results or approximations. Benchmarks with various concrete biological networks show that exact results can sometimes be obtained in networks with several hundred nodes. A class of even larger graphs can still be treated exactly by a new algorithm combining exhaustive and simple search strategies. For graphs, where the computation of exact solutions becomes time-consuming or infeasible, we devised an approximative algorithm with polynomial complexity. Strikingly, in realistic networks (where a comparison with exact results was possible this algorithm delivered results that are very close or equal to the exact values. This phenomenon can probably be attributed to the particular topology of cellular signaling and regulatory networks which contain a relatively low number of negative feedback loops. Conclusion The calculation of shortest positive

  14. Relativistic point interactions: Approximation by smooth potentials

    Science.gov (United States)

    Hughes, Rhonda J.

    1997-06-01

    We show that the four-parameter family of one-dimensional relativistic point interactions studied by Benvegnu and Dąbrowski may be approximated in the strong resolvent sense by smooth, local, short-range perturbations of the Dirac Hamiltonian. In addition, we prove that the nonrelativistic limits correspond to the Schrödinger point interactions studied extensively by the author and Paul Chernoff.

  15. Method and apparatus to image biological interactions in plants

    Science.gov (United States)

    Weisenberger, Andrew; Bonito, Gregory M.; Reid, Chantal D.; Smith, Mark Frederick

    2015-12-22

    A method to dynamically image the actual translocation of molecular compounds of interest in a plant root, root system, and rhizosphere without disturbing the root or the soil. The technique makes use of radioactive isotopes as tracers to label molecules of interest and to image their distribution in the plant and/or soil. The method allows for the study and imaging of various biological and biochemical interactions in the rhizosphere of a plant, including, but not limited to, mycorrhizal associations in such regions.

  16. Potential of biological images for radiation therapy of cancer

    International Nuclear Information System (INIS)

    Full text: Recent technical advances in 3D conformal and intensity modulated radiotherapy (3DCRT and IMRT) based, on patient-specific CT and MRI images, have the potential of delivering exquisitely conformal dose distributions to the target volume while avoiding critical structures. Emerging clinical results in terms of reducing treatment-related morbidity and increasing local control appear promising. Recent developments in imaging have suggested that biological images may further positively impact cancer diagnosis, characterization and therapy. While in the past radiological images are largely anatomical, the new types of images can provide metabolic, biochemical, physiological, functional and molecular (genotypic and phenotypic) information. For radiation therapy, images that give information about factors (e.g. tumor hypoxia, Tpot) that influence radiosensitivity and treatment outcome can be regarded as radiobiological images. The ability of IMRT to 'paint' (in 2D) or 'sculpt' (in 3D) the dose, and produce exquisitely conformal dose distributions begs the '64 million dollar question' as to how to paint or sculpt, and whether biological imaging may provide the pertinent information. Can this new approach provide 'radiobiological phenotypes' non-invasively, and incrementally improve upon the predictive assays of radiobiological characteristics such as proliferative activity (Tpot - the potential doubling time), radiosensitivity (SF2 - the surviving fraction at a dose of 2 Gy), energy status (relative to sublethal damage repair), pH (a possible surrogate of hypoxia), tumor hypoxia, etc. as prognosticator(s) of radiation treatment outcome. Important for IMRT, the spatial (geometrical) distribution of the radiobiological phenotypes provide the basis for dose distribution design to conform to both the physical (geometrical) and the biological attributes. Copyright (2001) Australasian College of Physical Scientists and Engineers in Medicine

  17. Passing messages between biological networks to refine predicted interactions.

    Directory of Open Access Journals (Sweden)

    Kimberly Glass

    Full Text Available Regulatory network reconstruction is a fundamental problem in computational biology. There are significant limitations to such reconstruction using individual datasets, and increasingly people attempt to construct networks using multiple, independent datasets obtained from complementary sources, but methods for this integration are lacking. We developed PANDA (Passing Attributes between Networks for Data Assimilation, a message-passing model using multiple sources of information to predict regulatory relationships, and used it to integrate protein-protein interaction, gene expression, and sequence motif data to reconstruct genome-wide, condition-specific regulatory networks in yeast as a model. The resulting networks were not only more accurate than those produced using individual data sets and other existing methods, but they also captured information regarding specific biological mechanisms and pathways that were missed using other methodologies. PANDA is scalable to higher eukaryotes, applicable to specific tissue or cell type data and conceptually generalizable to include a variety of regulatory, interaction, expression, and other genome-scale data. An implementation of the PANDA algorithm is available at www.sourceforge.net/projects/panda-net.

  18. The potential of standards-based agriculture biology as an alternative to traditional biology in California

    Science.gov (United States)

    Sellu, George Sahr

    schools. Thoron & Meyer (2011) suggested that research into the contribution of integrated science courses toward higher test scores yielded mixed results. This finding may have been due in part to the fact that integrated science courses only incorporate select topics into agriculture education courses. In California, however, agriculture educators have developed standards-based courses such as Agriculture Biology (AgBio) that cover the same content standards as core traditional courses such as traditional biology. Students in both AgBio and traditional biology take the same standardized biology test. This is the first time there has been an opportunity for a fair comparison and a uniform metric for an agriscience course such as AgBio to be directly compared to traditional biology. This study will examine whether there are differences between AgBio and traditional biology with regard to standardized test scores in biology. Furthermore, the study examines differences in perception between teachers and students regarding teaching and learning activities associated with higher achievement in science. The findings of the study could provide a basis for presenting AgBio as a potential alternative to traditional biology. The findings of this study suggest that there are no differences between AgBio and traditional biology students with regard to standardized biology test scores. Additionally, the findings indicate that co-curricular activities in AgBio could contribute higher student achievement in biology. However, further research is required to identify specific activities in AgBio that contribute to higher achievement in science.

  19. Deciphering The Complex Biological Interactions Of Nitric Oxide In Cancer

    Directory of Open Access Journals (Sweden)

    S. Perwez Hussain

    2015-08-01

    Full Text Available NO• is a free radical and is involved in a number of critical physiological processes including vasodilation, neurotransmission, immune regulation and inflammation. There are convincing evidence suggesting a role of NO• in the development and progression of different cancer types. However, the role of NO• in tumorigenesis is highly complex and both pro- and anti-neoplastic functions have been reported, which largely depends on the amount of NO•, cell types, cellular microenvironment, its interaction with other reactive species and presence of metals. An interesting interaction occurs between NO• and p53 tumor suppressor, in which NO•-induced DNA damage causes the stabilization and accumulation of p53, which in turn, transrepresses inducible nitric oxide synthase (NOS2 in a negative feedback loop. In chronic inflammatory diseases, for example ulcerative colitis, NO• induces p53 stabilization and the initiation of DNA-damage response pathway, and also generation of p53 mutation and subsequent clonal selection of p53 mutant cells. Genetic deletion of NOS2 in p53-deficient mice can either suppress or enhance lymphomagenesis depending on the inflammatory microenvironment. These findings highlight the importance of understanding the complex biological interaction of NO• in the context of the molecular makeup of each individual cancer to design NO•-targeted treatment strategies.

  20. Fungal phytotoxins with potential herbicidal activity: chemical and biological characterization.

    Science.gov (United States)

    Cimmino, Alessio; Masi, Marco; Evidente, Marco; Superchi, Stefano; Evidente, Antonio

    2015-12-19

    Covering: 2007 to 2015 Fungal phytotoxins are secondary metabolites playing an important role in the induction of disease symptoms interfering with host plant physiological processes. Although fungal pathogens represent a heavy constraint for agrarian production and for forest and environmental heritage, they can also represent an ecofriendly alternative to manage weeds. Indeed, the phytotoxins produced by weed pathogenic fungi are an efficient tool to design natural, safe bioherbicides. Their use could avoid that of synthetic pesticides causing resistance in the host plants and the long term impact of residues in agricultural products with a risk to human and animal health. The isolation and structural and biological characterization of phytotoxins produced by pathogenic fungi for weeds, including parasitic plants, are described. Structure activity relationships and mode of action studies for some phytotoxins are also reported to elucidate the herbicide potential of these promising fungal metabolites. PMID:26443032

  1. Potential Flow Interactions With Directional Solidification

    Science.gov (United States)

    Buddhavarapu, Sudhir S.; Meiburg, Eckart

    1999-01-01

    The effect of convective melt motion on the growth of morphological instabilities in crystal growth has been the focus of many studies in the past decade. While most of the efforts have been directed towards investigating the linear stability aspects, relatively little attention has been devoted to experimental and numerical studies. In a pure morphological case, when there is no flow, morphological changes in the solid-liquid interface are governed by heat conduction and solute distribution. Under the influence of a convective motion, both heat and solute are redistributed, thereby affecting the intrinsic morphological phenomenon. The overall effect of the convective motion could be either stabilizing or destabilizing. Recent investigations have predicted stabilization by a flow parallel to the interface. In the case of non-parallel flows, e.g., stagnation point flow, Brattkus and Davis have found a new flow-induced morphological instability that occurs at long wavelengths and also consists of waves propagating against the flow. Other studies have addressed the nonlinear aspects (Konstantinos and Brown, Wollkind and Segel)). In contrast to the earlier studies, our present investigation focuses on the effects of the potential flow fields typically encountered in Hele-Shaw cells. Such a Hele-Shaw cell can simulate a gravity-free environment in the sense that buoyancy-driven convection is largely suppressed, and hence negligible. Our interest lies both in analyzing the linear stability of the solidification process in the presence of potential flow fields, as well as in performing high-accuracy nonlinear simulations. Linear stability analysis can be performed for the flow configuration mentioned above. It is observed that a parallel potential flow is stabilizing and gives rise to waves traveling downstream. We have built a highly accurate numerical scheme which is validated at small amplitudes by comparing with the analytically predicted results for the pure

  2. Van der Waals interactions: accuracy of pair potential approximations.

    Science.gov (United States)

    Cole, Milton W; Kim, Hye-Young; Liebrecht, Michael

    2012-11-21

    Van der Waals interactions between single atoms and solids are discussed for the regime of large separation. A commonly employed approximation is to evaluate this interaction as a sum of two-body interactions between the adatom and the constituent atoms of the solid. The resulting potentials are here compared with known results in various geometries. Analogous comparisons are made for diatomic molecules near either single atoms or semi-infinite surfaces and for triatomic molecules' interactions with single atoms. PMID:23181315

  3. Large potential steps at weakly interacting metal-insulator interfaces

    OpenAIRE

    Bokdam, Menno; Brocks, Geert; Kelly, Paul J.

    2014-01-01

    Potential steps exceeding 1 eV are regularly formed at metal|insulator interfaces, even when the interaction between the materials at the interface is weak physisorption. From first-principles calculations on metal|h-BN interfaces we show that these potential steps are only indirectly sensitive to the interface bonding through the dependence of the binding energy curves on the van der Waals interaction. Exchange repulsion forms the main contribution to the interface potential step in the weak...

  4. Perception of social interactions for spatially scrambled biological motion.

    Science.gov (United States)

    Thurman, Steven M; Lu, Hongjing

    2014-01-01

    It is vitally important for humans to detect living creatures in the environment and to analyze their behavior to facilitate action understanding and high-level social inference. The current study employed naturalistic point-light animations to examine the ability of human observers to spontaneously identify and discriminate socially interactive behaviors between two human agents. Specifically, we investigated the importance of global body form, intrinsic joint movements, extrinsic whole-body movements, and critically, the congruency between intrinsic and extrinsic motions. Motion congruency is hypothesized to be particularly important because of the constraint it imposes on naturalistic action due to the inherent causal relationship between limb movements and whole body motion. Using a free response paradigm in Experiment 1, we discovered that many naïve observers (55%) spontaneously attributed animate and/or social traits to spatially-scrambled displays of interpersonal interaction. Total stimulus motion energy was strongly correlated with the likelihood that an observer would attribute animate/social traits, as opposed to physical/mechanical traits, to the scrambled dot stimuli. In Experiment 2, we found that participants could identify interactions between spatially-scrambled displays of human dance as long as congruency was maintained between intrinsic/extrinsic movements. Violating the motion congruency constraint resulted in chance discrimination performance for the spatially-scrambled displays. Finally, Experiment 3 showed that scrambled point-light dancing animations violating this constraint were also rated as significantly less interactive than animations with congruent intrinsic/extrinsic motion. These results demonstrate the importance of intrinsic/extrinsic motion congruency for biological motion analysis, and support a theoretical framework in which early visual filters help to detect animate agents in the environment based on several fundamental

  5. Biological efficiency of interaction between various radiation and chemicals

    International Nuclear Information System (INIS)

    This research project has been carried out jointly with INP (Poland) to develop technologies to assess the biological efficiency of interaction between radiation and chemicals. Through the cooperative project, KAERI and INP have established wide variety of bioassay techniques applicable to radiation bioscience, human monitoring, molecular epidemiology and environmental science. The joint experiment, in special, made it possible to utilize the merits of both institutes and to upgrade and verify KAERI's current technology level. All results of the cooperative research will be jointly published in high standard scientific journals listed in the Science Citation Index (SCI), which can make the role of fundamental basis for improving relationship between Korea and Poland. Research skills such as Trad-MCN assay, SCGE assay, immunohistochemical assay and molecular assay developed through joint research will be further elaborated and will be continuously used for the collaboration between two institutes

  6. Inferring Pairwise Interactions from Biological Data Using Maximum-Entropy Probability Models.

    Directory of Open Access Journals (Sweden)

    Richard R Stein

    2015-07-01

    Full Text Available Maximum entropy-based inference methods have been successfully used to infer direct interactions from biological datasets such as gene expression data or sequence ensembles. Here, we review undirected pairwise maximum-entropy probability models in two categories of data types, those with continuous and categorical random variables. As a concrete example, we present recently developed inference methods from the field of protein contact prediction and show that a basic set of assumptions leads to similar solution strategies for inferring the model parameters in both variable types. These parameters reflect interactive couplings between observables, which can be used to predict global properties of the biological system. Such methods are applicable to the important problems of protein 3-D structure prediction and association of gene-gene networks, and they enable potential applications to the analysis of gene alteration patterns and to protein design.

  7. Prospective study on microscopic potential with Gogny interaction

    Energy Technology Data Exchange (ETDEWEB)

    Blanchon, G.; Dupuis, M. [DAM, DIF, CEA, Arpajon (France); Arellano, H.F. [University of Chile, Department of Physics - FCFM, Santiago (Chile); DAM, DIF, CEA, Arpajon (France)

    2015-12-15

    We present our current studies and future plans on microscopic potential based on effective nucleon-nucleon interaction and many-body theory. This framework treats in an unified way nuclear structure and reaction. It offers the opportunity to link the underlying effective interaction to nucleon scattering observables. The more consistently connected to a variety of reaction and structure experimental data the framework is, the more constrained the effective interaction will be. As a proof of concept, we present some recent results for both neutron and proton scattered from spherical target nucleus, namely {sup 40}Ca, using the Gogny D1S interaction. Possible fruitful cross-talks between microscopic potential, phenomenological potential and effective interaction are exposed. We then draw some prospective plans for the forthcoming years including scattering from spherical nuclei experiencing pairing correlations, scattering from axially deformed nuclei, and new effective interaction with reaction constraints. (orig.)

  8. DNA triple helices: biological consequences and therapeutic potential.

    Science.gov (United States)

    Jain, Aklank; Wang, Guliang; Vasquez, Karen M

    2008-08-01

    DNA structure is a critical element in determining its function. The DNA molecule is capable of adopting a variety of non-canonical structures, including three-stranded (i.e. triplex) structures, which will be the focus of this review. The ability to selectively modulate the activity of genes is a long-standing goal in molecular medicine. DNA triplex structures, either intermolecular triplexes formed by binding of an exogenously applied oligonucleotide to a target duplex sequence, or naturally occurring intramolecular triplexes (H-DNA) formed at endogenous mirror repeat sequences, present exploitable features that permit site-specific alteration of the genome. These structures can induce transcriptional repression and site-specific mutagenesis or recombination. Triplex-forming oligonucleotides (TFOs) can bind to duplex DNA in a sequence-specific fashion with high affinity, and can be used to direct DNA-modifying agents to selected sequences. H-DNA plays important roles in vivo and is inherently mutagenic and recombinogenic, such that elements of the H-DNA structure may be pharmacologically exploitable. In this review we discuss the biological consequences and therapeutic potential of triple helical DNA structures. We anticipate that the information provided will stimulate further investigations aimed toward improving DNA triplex-related gene targeting strategies for biotechnological and potential clinical applications. PMID:18331847

  9. [Adhesive cell interactions in the biology of cancer].

    Science.gov (United States)

    Bocharova, O A

    2002-01-01

    The present review describes a hypothesis for a critical role of cell adhesive interactions in tumorigenesis. Dysregulation of tissue cell-cell interactions initiates first of all local (in the tissue) and then general (in whole body) conditions for tumor growth. Otherwise imbalance of tissue-specific adhesion factor at the very beginning of carcinogenesis is considered to trigger a cascade of pathological reactions responsible for more severe adhesive disorders that are in turn critical for the "totalitarian" behavior of a tumor and its "colonization" of other tissues and organs. Impaired disturbance is likely to be the key mechanism of carcinogenesis since it is significantly associated with the main features of a tumor: tissue proliferation control loss, anaplasia, invasion, metastasis, and immune surveillance deficit. The hypothesis is supported by evolutionary, biological, histological, immunological, and clinical arguments whose combination does not characterize any other known mechanisms of oncogenesis. The concept of adhesiveness opens new possibilities for the diagnosis, prevention, and treatment of tumors and also improves a strategy for designing new drugs.

  10. Symmetrical charge-charge interactions in ionic solutions: implications for biological interactions

    CERN Document Server

    Faraggi, Eshel

    2012-01-01

    As is well known in electrolyte theory, electrostatic fields are attenuated by the presence of mobile charges in the solution. This seems to limit the possibility of an electrostatic repulsion model of biological interactions such as cell division. Here, a system of two charges in an ionic solution is considered. It is found that in the context of the symmetries of the system, the electrostatic repulsion between the two is considerably increased as compared to the electrostatic repulsion between two bare charges in a dielectric. This increase in repulsion, directly resulting from interactions between the symmetrical parts of the system, was found to be dependent on the magnitude of the charges and the separation between them. It was also found that this increases reaches a steady state for separation greater than a solvent determined length scale related to the Debye length. These findings strongly suggest that electrostatic interactions can play a crucial part in the physical forces that are involved in biol...

  11. Primate paternal care: interactions between biology and social experience

    Science.gov (United States)

    Storey, Anne E.; Ziegler, Toni E.

    2016-01-01

    We review recent research on the roles of hormones and social experiences on the development of paternal care in humans and non-human primates. Generally, lower concentrations of testosterone and higher concentrations of oxytocin are associated with greater paternal responsiveness. Hormonal changes prior to the birth appear to be important in preparation for fatherhood and changes after the birth are related to how much time fathers spend with offspring and whether they provide effective care. Prolactin may facilitate approach and the initiation of infant care, and in some biparental non-human primates, it affects body mass regulation. Glucocorticoids are involved in coordinating reproductive and parental behavior between mates. New research involving intranasal oxytocin and neuropeptide receptor polymorphisms may help us understand individual variation in paternal responsiveness. This area of research, integrating both biological factors and the role of early and adult experience, has the potential to suggest individually designed interventions that can strengthen relationships between fathers and their offspring. PMID:26253726

  12. Parasites and biological invasions: parallels, interactions, and control.

    Science.gov (United States)

    Dunn, Alison M; Hatcher, Melanie J

    2015-05-01

    Species distributions are changing at an unprecedented rate owing to human activity. We examine how two key processes of redistribution - biological invasion and disease emergence - are interlinked. There are many parallels between invasion and emergence processes, and invasions can drive the spread of new diseases to wildlife. We examine the potential impacts of invasion and disease emergence, and discuss how these threats can be countered, focusing on biosecurity. In contrast with international policy on emerging diseases of humans and managed species, policy on invasive species and parasites of wildlife is fragmented, and the lack of international cooperation encourages individual parties to minimize their input into control. We call for international policy that acknowledges the strong links between emerging diseases and invasion risk.

  13. Calculation of Interaction Potentials between Spherical and Deformed Nuclei

    Institute of Scientific and Technical Information of China (English)

    ZHANG Gao-Long; XU Xin-Xing; BAI Chun-Lin; YU Ning; ZHANG Huan-Qiao; LIU Zu-Hua; ZHANG Chun-Lei; LIN Cheng-Jian; YANG Feng; AN Guang-Peng; JIA Hui-Ming; WU Zhen-Dong

    2007-01-01

    The interaction potential for spherical-deformed reaction partners is calculated. The shape, separation and orientation dependence of the interaction potential and fusion cross section of the system 32S+154Sm are investigated within the double-folding model of the deformed nuclei. The effective nucleon-nucleon interaction is taken to be the M3Y-Reid potential. The density is considered for three terms of the expansion using the truncated multipole expansion method, which is a deformed Fermi shape with quadrupole and hexadecapole for the density distribution of 154Sm. It is found for the interaction potential that the height and the position of barrier strongly depend on the deformations, the orientation angle of the deformed nucleus, and hence produce great effects on fusion cross section. The integrated fusion cross section is in good agreement with the experimental data.

  14. Helium-3 Microscopic Optical Model Potential Based on Skyrme Interaction

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>The helium-3 microscopic optical potential is obtained by Green function method through nuclear matter approximation and local density approximation based on the effective Skyrme interaction. The reaction cross

  15. Potential of Biological Agents in Decontamination of Agricultural Soil.

    Science.gov (United States)

    Javaid, Muhammad Kashif; Ashiq, Mehrban; Tahir, Muhammad

    2016-01-01

    Pesticides are widely used for the control of weeds, diseases, and pests of cultivated plants all over the world, mainly since the period after the Second World War. The use of pesticides is very extensive to control harm of pests all over the globe. Persistent nature of most of the synthetic pesticides causes serious environmental concerns. Decontamination of these hazardous chemicals is very essential. This review paper elaborates the potential of various biological agents in decontamination of agricultural soils. The agricultural crop fields are contaminated by the periodic applications of pesticides. Biodegradation is an ecofriendly, cost-effective, highly efficient approach compared to the physical and chemical methods which are expensive as well as unfriendly towards environment. Biodegradation is sensitive to the concentration levels of hydrogen peroxide and nitrogen along with microbial community, temperature, and pH changes. Experimental work for optimum conditions at lab scale can provide very fruitful results about specific bacterial, fungal strains. This study revealed an upper hand of bioremediation over physicochemical approaches. Further studies should be carried out to understand mechanisms of biotransformation. PMID:27293964

  16. Potential of Biological Agents in Decontamination of Agricultural Soil

    Science.gov (United States)

    Javaid, Muhammad Kashif; Ashiq, Mehrban; Tahir, Muhammad

    2016-01-01

    Pesticides are widely used for the control of weeds, diseases, and pests of cultivated plants all over the world, mainly since the period after the Second World War. The use of pesticides is very extensive to control harm of pests all over the globe. Persistent nature of most of the synthetic pesticides causes serious environmental concerns. Decontamination of these hazardous chemicals is very essential. This review paper elaborates the potential of various biological agents in decontamination of agricultural soils. The agricultural crop fields are contaminated by the periodic applications of pesticides. Biodegradation is an ecofriendly, cost-effective, highly efficient approach compared to the physical and chemical methods which are expensive as well as unfriendly towards environment. Biodegradation is sensitive to the concentration levels of hydrogen peroxide and nitrogen along with microbial community, temperature, and pH changes. Experimental work for optimum conditions at lab scale can provide very fruitful results about specific bacterial, fungal strains. This study revealed an upper hand of bioremediation over physicochemical approaches. Further studies should be carried out to understand mechanisms of biotransformation. PMID:27293964

  17. Potential of Biological Agents in Decontamination of Agricultural Soil

    Directory of Open Access Journals (Sweden)

    Muhammad Kashif Javaid

    2016-01-01

    Full Text Available Pesticides are widely used for the control of weeds, diseases, and pests of cultivated plants all over the world, mainly since the period after the Second World War. The use of pesticides is very extensive to control harm of pests all over the globe. Persistent nature of most of the synthetic pesticides causes serious environmental concerns. Decontamination of these hazardous chemicals is very essential. This review paper elaborates the potential of various biological agents in decontamination of agricultural soils. The agricultural crop fields are contaminated by the periodic applications of pesticides. Biodegradation is an ecofriendly, cost-effective, highly efficient approach compared to the physical and chemical methods which are expensive as well as unfriendly towards environment. Biodegradation is sensitive to the concentration levels of hydrogen peroxide and nitrogen along with microbial community, temperature, and pH changes. Experimental work for optimum conditions at lab scale can provide very fruitful results about specific bacterial, fungal strains. This study revealed an upper hand of bioremediation over physicochemical approaches. Further studies should be carried out to understand mechanisms of biotransformation.

  18. Intermolecular interaction of thiosemicarbazone derivatives to solvents and a potential Aedes aegypti target

    Science.gov (United States)

    da Silva, João Bosco P.; Hallwass, Fernando; da Silva, Aluizio G.; Moreira, Diogo Rodrigo; Ramos, Mozart N.; Espíndola, José Wanderlan P.; de Oliveira, Ana Daura T.; Brondani, Dalci José; Leite, Ana Cristina L.; Merz, Kenneth M.

    2015-08-01

    DFT calculations were used to access information about structure, energy and electronic properties of series of phenyl- and phenoxymethyl-(thio)semicarbazone derivatives with demonstrated activity against the larvae of Aedes aegypti in stage L4. The way as the thiosemicarbazone derivatives can interact with solvents like DMSO and water were analyzed from the comparison between calculated and experimental 1H NMR chemical shifts. The evidences of thiosemicarbazone derivatives making H-bond interaction to solvent have provide us insights on how they can interact with a potential A. aegypti's biological target, the Sterol Carrier Protein-2.

  19. Synthesis of potentially bioactive compounds and tools for biological studies

    International Nuclear Information System (INIS)

    preparative scale may potentially increase the specificity and biological activity of these carbohydrates and deepen the understanding of glycobiology in the research of new medicines. (author)

  20. An interatomic potential for W–N interactions

    Science.gov (United States)

    Polvi, J.; Heinola, K.; Nordlund, K.

    2016-08-01

    N2 gas is routinely used as a seeding species in fusion plasma to control the amount of power emitted from the plasma by radiation to the tungsten walls of an ITER-like divertor. Nitrogen atoms interact with the plasma-facing materials beryllium and tungsten, and form chemical bonds with the wall surfaces, as well as with plasma hydrogen isotopes, thus raising a special interest in W–N and N–H interactions in the fusion community. In this work we describe the development of an analytical interatomic potential for W–N interactions and benchmark the potential against DFT calculation results for N defects in tungsten.

  1. Microbiology and atmospheric processes: chemical interactions of primary biological aerosols

    Directory of Open Access Journals (Sweden)

    L. Deguillaume

    2008-07-01

    Full Text Available This paper discusses the influence of primary biological aerosols (PBA on atmospheric chemistry and vice versa through microbiological and chemical properties and processes. Several studies have shown that PBA represent a significant fraction of air particulate matter and hence affect the microstructure and water uptake of aerosol particles. Moreover, airborne micro-organisms, namely fungal spores and bacteria, can transform chemical constituents of the atmosphere by metabolic activity. Recent studies have emphasized the viability of bacteria and metabolic degradation of organic substances in cloud water. On the other hand, the viability and metabolic activity of airborne micro-organisms depend strongly on physical and chemical atmospheric parameters such as temperature, pressure, radiation, pH value and nutrient concentrations. In spite of recent advances, however, our knowledge of the microbiological and chemical interactions of PBA in the atmosphere is rather limited. Further targeted investigations combining laboratory experiments, field measurements, and modelling studies will be required to characterize the chemical feedbacks, microbiological activities at the air/snow/water interface supplied to the atmosphere.

  2. Biokinetics of zinc oxide nanoparticles: toxicokinetics, biological fates, and protein interaction

    Directory of Open Access Journals (Sweden)

    Choi SJ

    2014-12-01

    Full Text Available Soo-Jin Choi,1 Jin-Ho Choy2 1Department of Food Science and Technology, Seoul Women's University, 2Center for Intelligent Nano Bio Materials (CINBM, Department of Bioinspired Science and Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, South Korea Abstract: Biokinetic studies of zinc oxide (ZnO nanoparticles involve systematic and quantitative analyses of absorption, distribution, metabolism, and excretion in plasma and tissues of whole animals after exposure. A full understanding of the biokinetics provides basic information about nanoparticle entry into systemic circulation, target organs of accumulation and toxicity, and elimination time, which is important for predicting the long-term toxic potential of nanoparticles. Biokinetic behaviors can be dependent on physicochemical properties, dissolution property in biological fluids, and nanoparticle–protein interaction. Moreover, the determination of biological fates of ZnO nanoparticles in the systemic circulation and tissues is critical in interpreting biokinetic behaviors and predicting toxicity potential as well as mechanism. This review focuses on physicochemical factors affecting the biokinetics of ZnO nanoparticles, in concert with understanding bioavailable fates and their interaction with proteins. Keywords: ZnO nanoparticles, biokinetics, distribution, excretion, fate, interaction

  3. Factors Potentially Influencing Student Acceptance of Biological Evolution

    Science.gov (United States)

    Wiles, Jason R.

    This investigation explored scientific, religious, and otherwise nonscientific factors that may influence student acceptance of biological evolution and related concepts, how students perceived these factors to have influenced their levels of acceptance of evolution and changes therein, and what patterns arose among students' articulations of how their levels of acceptance of evolution may have changed. This exploration also measured the extent to which students' levels of acceptance changed following a treatment designed to address factors identified as potentially affecting student acceptance of evolution. Acceptance of evolution was measured using the MATE instrument (Rutledge and Warden, 1999; Rutledge and Sadler, 2007) among participants enrolled in a secondary-level academic program during the summer prior to their final year of high school and as they transitioned to the post-secondary level. Student acceptance of evolution was measured to be significantly higher than pre-treatment levels both immediately following and slightly over one year after treatment. Qualitative data from informal questionnaires, from formal course evaluations, and from semi-structured interviews of students engaged in secondary level education and former students at various stages of post-secondary education confirmed that the suspected factors were perceived by participants to have influenced their levels of acceptance of evolution. Furthermore, participant reports provided insight regarding the relative effects they perceived these factors to have had on their evolution acceptance levels. Additionally, many participants reported that their science teachers in public schools had avoided, omitted, or denigrated evolution during instruction, and several of these students expressed frustration regarding what they perceived to have been a lack of education of an important scientific principle. Finally, no students expressed feelings of being offended by having been taught about

  4. Risk factors for potential drug interactions in general practice

    DEFF Research Database (Denmark)

    Bjerrum, Lars; Gonzalez Lopez-Valcarcel, Beatriz; Petersen, Gert

    2008-01-01

    Objective: To identify patient- and practice-related factors associated with potential drug interactions. Methods: A register analysis study in general practices in the county of Funen, Denmark. Prescription data were retrieved from a population-based prescription database (Odense University...... Pharmacoepidemiologic Database, OPED) covering prescriptions to all inhabitants in the county of Funen, Denmark. All individuals exposed to concurrent use of two or more drugs (polypharmacy) were identified. Combinations of drugs with potential interactions were registered and classified as major, moderate, or minor......, depending on the severity of outcome and the quality of documentation. A two-level random coefficient logistic regression model was used to investigate factors related to potential drug interactions. Results: One-third of the population was exposed to polypharmacy, and 6% were exposed to potential drug...

  5. Isospectral Bound State Potential from DDM3Y Effective Interaction

    CERN Document Server

    Dutta, S K; Das, D; Saha, Swapan K

    2013-01-01

    Theoretical investigation of ${5/2}^+$ resonance state of $^{11}Be$ was carried out using Supersymmetric Quantum Mechanics (SQM). The original two-body potential ($^{10}Be + n$) was constructed microscopically using a DDM3Y effective NN interaction. SQM converted this potential to an isospectral potential which is effective for detecting resonance states in the continuum. The resonance energy of the ${5/2}^+$ state is in good agreement with the experimental value.

  6. Usefulness and limitations of dK random graph models to predict interactions and functional homogeneity in biological networks under a pseudo-likelihood parameter estimation approach

    OpenAIRE

    Luan Yihui; Nunez-Iglesias Juan; Wang Wenhui; Sun Fengzhu

    2009-01-01

    Abstract Background Many aspects of biological functions can be modeled by biological networks, such as protein interaction networks, metabolic networks, and gene coexpression networks. Studying the statistical properties of these networks in turn allows us to infer biological function. Complex statistical network models can potentially more accurately describe the networks, but it is not clear whether such complex models are better suited to find biologically meaningful subnetworks. Results ...

  7. Expression Patterns and Potential Biological Roles of Dip2a.

    Directory of Open Access Journals (Sweden)

    Luqing Zhang

    Full Text Available Disconnected (disco-interacting protein 2 homolog A is a member of the DIP2 protein family encoded by Dip2a gene. Dip2a expression pattern has never been systematically studied. Functions of Dip2a in embryonic development and adult are not known. To investigate Dip2a gene expression and function in embryo and adult, a Dip2a-LacZ mouse model was generated by insertion of β-Gal cDNA after Dip2a promoter using CRISPR/Cas9 technology. Dip2a-LacZ mouse was designed to be a lacZ reporter mouse as well as a Dip2a knockout mouse. Heterozygous mice were used to study endogenous Dip2a expression and homozygotes to study DIP2A-associated structure and function. LacZ staining indicated that Dip2a is broadly expressed in neuronal, reproductive and vascular tissues, as well as in heart, kidney, liver and lung. Results demonstrate that Dip2a is expressed in ectoderm-derived tissues in developing embryos. Adult tissues showed rich staining in neurons, mesenchymal, endothelial, smooth muscle cells and cardiomyocytes by cell types. The expression pattern highly overlaps with FSTL1 and supports previous report that DIP2A to be potential receptor of FSTL1 and its protective roles of cardiomyocytes. Broad and intense embryonic and adult expression of Dip2a has implied their multiple structural and physiological roles.

  8. Biological General Repository for Interaction Datasets (BioGRID)

    Data.gov (United States)

    U.S. Department of Health & Human Services — BioGRID is an online interaction repository with data on raw protein and genetic interactions from major model organism species. All interaction data are freely...

  9. On the remote interaction of biological objects with identical genetic structures

    CERN Document Server

    Berkovich, S Y

    2002-01-01

    The paper puts forward an unusual prediction that cultivating a clone can curtail the lifespan of the clone donor. Neither the arrangement of this suggested empirical study nor the analyses of the anticipated outcomes rely on the accompanying theoretical contemplations. This prediction has come from the interpretation of the genome as a "barcode". The genome is considered as an identification label rather than a repository of control information, so living beings are portrayed as a community of users on the "Internet of the physical Universe". Thus, biological objects with identical (or nearly identical) DNA structures can interfere, and the surmised remote impact appears tangible. The effect of clone-donor interaction leads to a decisive Experimentum Crucis that can reject the common view on the organization of biological information processing. Exploitation of this effect can be potentially dangerous.

  10. Primate paternal care: Interactions between biology and social experience.

    Science.gov (United States)

    Storey, Anne E; Ziegler, Toni E

    2016-01-01

    This article is part of a Special Issue "Parental Care".We review recent research on the roles of hormones and social experiences on the development of paternal care in humans and non-human primates. Generally, lower concentrations of testosterone and higher concentrations of oxytocin are associated with greater paternal responsiveness. Hormonal changes prior to the birth appear to be important in preparation for fatherhood and changes after the birth are related to how much time fathers spend with offspring and whether they provide effective care. Prolactin may facilitate approach and the initiation of infant care, and in some biparental non-human primates, it affects body mass regulation. Glucocorticoids may be involved in coordinating reproductive and parental behavior between mates. New research involving intranasal oxytocin and neuropeptide receptor polymorphisms may help us understand individual variation in paternal responsiveness. This area of research, integrating both biological factors and the role of early and adult experience, has the potential to suggest individually designed interventions that can strengthen relationships between fathers and their partners and offspring. PMID:26253726

  11. Rare taxa have potential to make metabolic contributions in enhanced biological phosphorus removal ecosystems.

    Science.gov (United States)

    Lawson, Christopher E; Strachan, Blake J; Hanson, Niels W; Hahn, Aria S; Hall, Eric R; Rabinowitz, Barry; Mavinic, Donald S; Ramey, William D; Hallam, Steven J

    2015-12-01

    Enhanced biological phosphorus removal (EBPR) relies on diverse but specialized microbial communities to mediate the cycling and ultimate removal of phosphorus from municipal wastewaters. However, little is known about microbial activity and dynamics in relation to process fluctuations in EBPR ecosystems. Here, we monitored temporal changes in microbial community structure and potential activity across each bioreactor zone in a pilot-scale EBPR treatment plant by examining the ratio of small subunit ribosomal RNA (SSU rRNA) to SSU rRNA gene (rDNA) over a 120 day study period. Although the majority of operational taxonomic units (OTUs) in the EBPR ecosystem were rare, many maintained high potential activities based on SSU rRNA : rDNA ratios, suggesting that rare OTUs contribute substantially to protein synthesis potential in EBPR ecosystems. Few significant differences in OTU abundance and activity were observed between bioreactor redox zones, although differences in temporal activity were observed among phylogenetically cohesive OTUs. Moreover, observed temporal activity patterns could not be explained by measured process parameters, suggesting that other ecological drivers, such as grazing or viral lysis, modulated community interactions. Taken together, these results point towards complex interactions selected for within the EBPR ecosystem and highlight a previously unrecognized functional potential among low abundance microorganisms in engineered ecosystems. PMID:25857222

  12. Interaction potential between discrete solitons in waveguide arrays.

    Science.gov (United States)

    Al Khawaja, U; Al-Marzoug, S M; Bahlouli, H; Baizakov, B

    2016-08-01

    Using a variational approach, we obtained the interaction potential between two discrete solitons in optical waveguide arrays. The resulting potential bears the two features of soliton-soliton and soliton-waveguide interaction potentials where the former is similar to that of the continuum case and the latter is similar to the effective Pierls-Nabarro potential. The interplay between the two interaction potentials is investigated by studying its effect on the soliton molecule formation. It is found that the two solitons bind if their initial separation equals an odd number of waveguides, while they do not bind if their separation is an even number, which is a consequence of the two solitons being both either at the intersites (unstable) or being onsite (stable). We derived the equations of motion for the solitons' centre of mass and relative separation and provided analytic solutions for some specific cases. Favourable agreement between the analytical and numerical interaction potentials is obtained. Possible applications of our results to all-optical logic gates are pointed out. PMID:27505780

  13. The interaction between potential criminals' and victims' demands for guns

    OpenAIRE

    Baç, Mehmet; Bac, Mehmet

    2009-01-01

    I develop a model with endogenous gun ownership and study the interaction between the demands for guns by heterogeneous potential offenders and victims. I show that the interaction depends on pervasiveness of guns, injury probabilities and, in particular, the impact of the gun on the probability of success against armed relative to unarmed adversaries. While the sanction on armed offense is maximal under plausible conditions, the sanction on unarmed offense balances direct deterrence benef...

  14. Scattering with absorptive interaction: Energy-dependent potentials

    Science.gov (United States)

    Cassing, W.; Stingl, M.; Weiguny, A.

    1983-05-01

    The energy dependence and analytic structure of the effective interaction for elastic scattering of composite particles are investigated using Feshbach's projection technique. A generalized Levinson theorem is established for complex, nonlocal, and energy-dependent interactions. The analytical results are illustrated by means of Argand diagrams for a solvable model and the effect of energy averaging is discussed. NUCLEAR REACTIONS Scattering theory, S matrix for absorptive, energy-dependent potentials, Levinson theorem.

  15. Generation of directional EOF by interactive oscillatory zeta potential.

    Science.gov (United States)

    Kuo, Chih-Yu; Wang, Chang-Yi; Chang, Chien-Cheng

    2008-11-01

    A steady directional EOF due to a nonlinear interaction between oscillatory axial electrical fields and oscillatory wall potentials (zeta potentials) is presented. This is a new mechanism to produce such a mean flow. It is found that the flow velocity depends not on the external driving frequency but on the phase angle difference between the electric fields and the zeta potentials. The formulation can also be reduced to the static EOF straightforwardly. For the purpose of theoretical demonstration, we use the Debye-Huckel approximation for the zeta potential. Results of planar and cylindrical capillaries are given.

  16. Molecular Insights into the Potential Toxicological Interaction of 2-Mercaptothiazoline with the Antioxidant Enzyme—Catalase

    OpenAIRE

    Zhenxing Huang; Ming Huang; Chenyu Mi; Tao Wang; Dong Chen; Yue Teng

    2016-01-01

    2-mercaptothiazoline (2-MT) is widely used in many industrial fields, but its residue is potentially harmful to the environment. In this study, to evaluate the biological toxicity of 2-MT at protein level, the interaction between 2-MT and the pivotal antioxidant enzyme—catalase (CAT) was investigated using multiple spectroscopic techniques and molecular modeling. The results indicated that the CAT fluorescence quenching caused by 2-MT should be dominated by a static quenching mechanism throug...

  17. Combining genomic sequencing methods to explore viral diversity and reveal potential virus-host interactions

    OpenAIRE

    Chow, Cheryl-Emiliane T.; Danielle M Winget; White, Richard A.; Steven J Hallam; Suttle, Curtis A.

    2015-01-01

    Viral diversity and virus-host interactions in oxygen-starved regions of the ocean, also known as oxygen minimum zones (OMZs), remain relatively unexplored. Microbial community metabolism in OMZs alters nutrient and energy flow through marine food webs, resulting in biological nitrogen loss and greenhouse gas production. Thus, viruses infecting OMZ microbes have the potential to modulate community metabolism with resulting feedback on ecosystem function. Here, we describe viral communities in...

  18. Interactions between delta-like sources and potentials

    CERN Document Server

    Camilo, G T; Barone, F A

    2014-01-01

    The modified scalar boson propagator due to the presence of a hyperplane semi-transparent mirror is computed. From this, the classical interaction between static charges and the mirror is investigated employing delta-like potentials and sources. Although the calculations for hyperplane mirrors are performed in arbitrary dimensions, and in a completely general way, it is shown that the results give rise to the usual image method as a particular case. The interaction between a point-like mirror and a point-like source is also considered in $3+1$ dimensions, where a central $1/R^{2}$ attractive potential is also obtained as a special case.

  19. Toward an interactive article: integrating journals and biological databases

    Directory of Open Access Journals (Sweden)

    Marygold Steven J

    2011-05-01

    Full Text Available Abstract Background Journal articles and databases are two major modes of communication in the biological sciences, and thus integrating these critical resources is of urgent importance to increase the pace of discovery. Projects focused on bridging the gap between journals and databases have been on the rise over the last five years and have resulted in the development of automated tools that can recognize entities within a document and link those entities to a relevant database. Unfortunately, automated tools cannot resolve ambiguities that arise from one term being used to signify entities that are quite distinct from one another. Instead, resolving these ambiguities requires some manual oversight. Finding the right balance between the speed and portability of automation and the accuracy and flexibility of manual effort is a crucial goal to making text markup a successful venture. Results We have established a journal article mark-up pipeline that links GENETICS journal articles and the model organism database (MOD WormBase. This pipeline uses a lexicon built with entities from the database as a first step. The entity markup pipeline results in links from over nine classes of objects including genes, proteins, alleles, phenotypes and anatomical terms. New entities and ambiguities are discovered and resolved by a database curator through a manual quality control (QC step, along with help from authors via a web form that is provided to them by the journal. New entities discovered through this pipeline are immediately sent to an appropriate curator at the database. Ambiguous entities that do not automatically resolve to one link are resolved by hand ensuring an accurate link. This pipeline has been extended to other databases, namely Saccharomyces Genome Database (SGD and FlyBase, and has been implemented in marking up a paper with links to multiple databases. Conclusions Our semi-automated pipeline hyperlinks articles published in GENETICS to

  20. Lichen-moss interactions within biological soil crusts

    Science.gov (United States)

    Ruckteschler, Nina; Williams, Laura; Büdel, Burkhard; Weber, Bettina

    2015-04-01

    Biological soil crusts (biocrusts) create well-known hotspots of microbial activity, being important components of hot and cold arid terrestrial regions. They colonize the uppermost millimeters of the soil, being composed of fungi, (cyano-) bacteria, algae, lichens, bryophytes and archaea in varying proportions. Biocrusts protect the (semi-) arid landscape from wind and water erosion, and also increase water holding capacity and nutrient content. Depending on location and developmental stage, composition and species abundance vary within biocrusts. As species live in close contact, they are expected to influence each other, but only a few interactions between different organisms have so far been explored. In the present study, we investigated the effects of the lichen Fulgensia fulgens whilst growing on the moss Trichostomum crispulum. While 77% of Fulgensia fulgens thalli were found growing associated with mosses in a German biocrust, up to 95% of Fulgensia bracteata thalli were moss-associated in a Swedish biocrust. In 49% (Germany) and in 78% (Sweden) of cases, thalli were observed on the moss T. crispulum and less frequently on four and three different moss species. Beneath F. fulgens and F. bracteata thalli, the mosses were dead and in close vicinity to the lichens the mosses appeared frail, bringing us to the assumption that the lichens may release substances harming the moss. We prepared a water extract from the lichen F. fulgens and used this to water the moss thalli (n = 6) on a daily basis over a time-span of three weeks. In a control setup, artificial rainwater was applied to the moss thalli (n = 6). Once a week, maximum CO2 gas exchange rates of the thalli were measured under constant conditions and at the end of the experiment the chlorophyll content of the moss samples was determined. In the course of the experiment net photosynthesis (NP) of the treatment samples decreased concurrently with an increase in dark respiration (DR). The control samples

  1. Bronchoconstriction and airway biology : potential impact and therapeutic opportunities

    NARCIS (Netherlands)

    Gosens, Reinoud; Grainge, Chris

    2015-01-01

    Recent work has demonstrated that mechanical forces occurring in the airway as a consequence of bronchoconstriction are sufficient to not only induce symptoms but also influence airway biology. Animal and human in vitro and in vivo work demonstrates that the airways are structurally and functionally

  2. Interacting Bose gas confined in a Kronig-Penney potential

    Science.gov (United States)

    Rodríguez, O. A.; Solís, M. A.

    We analyze the effect of the 1D periodic Kronig-Penney potential, composed of barriers of width b and separated a distance a, over an interacting Bose gas. At T = 0 , the Gross-Pitaevskii equation is solved analytically in terms of the Jacobi elliptic functions for repulsive or attractive interaction between bosons. By applying the boundary conditions for periodic solutions as well as the normalization of the wave function, we arrive to a set of nonlinear equations from which we obtain the density profile and the chemical potential of the condensate as a function of the particle momentum. The profiles for attractive and repulsive interactions are compared with that of the non-interacting case. For attractive interaction we are able to observe a pronounced spatial localization in the middle of every two barriers. We reproduce the well known results when the Kronig-Penney potential becomes a Dirac Comb. We acknowledge partial support from Grants PAPIIT IN111613 and CONACyT 221030.

  3. Market potential for interactive audio-visual media

    NARCIS (Netherlands)

    Leurdijk, A.; Limonard, S.

    2005-01-01

    NM2 (New Media for a New Millennium) develops tools for interactive, personalised and non-linear audio-visual content that will be tested in seven pilot productions. This paper looks at the market potential for these productions from a technological, a business and a users' perspective. It shows tha

  4. Optimizing Interacting Potentials to Form Targeted Materials Structures

    Energy Technology Data Exchange (ETDEWEB)

    Torquato, Salvatore [Princeton Univ., NJ (United States)

    2015-09-28

    Conventional applications of the principles of statistical mechanics (the "forward" problems), start with particle interaction potentials, and proceed to deduce local structure and macroscopic properties. Other applications (that may be classified as "inverse" problems), begin with targeted configurational information, such as low-order correlation functions that characterize local particle order, and attempt to back out full-system configurations and/or interaction potentials. To supplement these successful experimental and numerical "forward" approaches, we have focused on inverse approaches that make use of analytical and computational tools to optimize interactions for targeted self-assembly of nanosystems. The most original aspect of our work is its inherently inverse approach: instead of predicting structures that result from given interaction potentials among particles, we determine the optimal potential that most robustly stabilizes a given target structure subject to certain constraints. Our inverse approach could revolutionize the manner in which materials are designed and fabricated. There are a number of very tangible properties (e.g. zero thermal expansion behavior), elastic constants, optical properties for photonic applications, and transport properties.

  5. Analysis of Boolean Functions based on Interaction Graphs and their influence in System Biology

    OpenAIRE

    Das, Jayanta Kumar; Rout, Ranjeet Kumar; Choudhury, Pabitra Pal

    2014-01-01

    Interaction graphs provide an important qualitative modeling approach for System Biology. This paper presents a novel approach for construction of interaction graph with the help of Boolean function decomposition. Each decomposition part (Consisting of 2-bits) of the Boolean functions has some important significance. In the dynamics of a biological system, each variable or node is nothing but gene or protein. Their regulation has been explored in terms of interaction graphs which are generate...

  6. Potential disruption of protein-protein interactions by graphene oxide.

    Science.gov (United States)

    Feng, Mei; Kang, Hongsuk; Yang, Zaixing; Luan, Binquan; Zhou, Ruhong

    2016-06-14

    Graphene oxide (GO) is a promising novel nanomaterial with a wide range of potential biomedical applications due to its many intriguing properties. However, very little research has been conducted to study its possible adverse effects on protein-protein interactions (and thus subsequent toxicity to human). Here, the potential cytotoxicity of GO is investigated at molecular level using large-scale, all-atom molecular dynamics simulations to explore the interaction mechanism between a protein dimer and a GO nanosheet oxidized at different levels. Our theoretical results reveal that GO nanosheet could intercalate between the two monomers of HIV-1 integrase dimer, disrupting the protein-protein interactions and eventually lead to dimer disassociation as graphene does [B. Luan et al., ACS Nano 9(1), 663 (2015)], albeit its insertion process is slower when compared with graphene due to the additional steric and attractive interactions. This study helps to better understand the toxicity of GO to cell functions which could shed light on how to improve its biocompatibility and biosafety for its wide potential biomedical applications.

  7. Potential disruption of protein-protein interactions by graphene oxide

    Science.gov (United States)

    Feng, Mei; Kang, Hongsuk; Yang, Zaixing; Luan, Binquan; Zhou, Ruhong

    2016-06-01

    Graphene oxide (GO) is a promising novel nanomaterial with a wide range of potential biomedical applications due to its many intriguing properties. However, very little research has been conducted to study its possible adverse effects on protein-protein interactions (and thus subsequent toxicity to human). Here, the potential cytotoxicity of GO is investigated at molecular level using large-scale, all-atom molecular dynamics simulations to explore the interaction mechanism between a protein dimer and a GO nanosheet oxidized at different levels. Our theoretical results reveal that GO nanosheet could intercalate between the two monomers of HIV-1 integrase dimer, disrupting the protein-protein interactions and eventually lead to dimer disassociation as graphene does [B. Luan et al., ACS Nano 9(1), 663 (2015)], albeit its insertion process is slower when compared with graphene due to the additional steric and attractive interactions. This study helps to better understand the toxicity of GO to cell functions which could shed light on how to improve its biocompatibility and biosafety for its wide potential biomedical applications.

  8. Biologic

    CERN Document Server

    Kauffman, L H

    2002-01-01

    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  9. Predicting drug-target interaction networks based on functional groups and biological features.

    Directory of Open Access Journals (Sweden)

    Zhisong He

    Full Text Available BACKGROUND: Study of drug-target interaction networks is an important topic for drug development. It is both time-consuming and costly to determine compound-protein interactions or potential drug-target interactions by experiments alone. As a complement, the in silico prediction methods can provide us with very useful information in a timely manner. METHODS/PRINCIPAL FINDINGS: To realize this, drug compounds are encoded with functional groups and proteins encoded by biological features including biochemical and physicochemical properties. The optimal feature selection procedures are adopted by means of the mRMR (Maximum Relevance Minimum Redundancy method. Instead of classifying the proteins as a whole family, target proteins are divided into four groups: enzymes, ion channels, G-protein- coupled receptors and nuclear receptors. Thus, four independent predictors are established using the Nearest Neighbor algorithm as their operation engine, with each to predict the interactions between drugs and one of the four protein groups. As a result, the overall success rates by the jackknife cross-validation tests achieved with the four predictors are 85.48%, 80.78%, 78.49%, and 85.66%, respectively. CONCLUSION/SIGNIFICANCE: Our results indicate that the network prediction system thus established is quite promising and encouraging.

  10. Text mining and its potential applications in systems biology.

    Science.gov (United States)

    Ananiadou, Sophia; Kell, Douglas B; Tsujii, Jun-ichi

    2006-12-01

    With biomedical literature increasing at a rate of several thousand papers per week, it is impossible to keep abreast of all developments; therefore, automated means to manage the information overload are required. Text mining techniques, which involve the processes of information retrieval, information extraction and data mining, provide a means of solving this. By adding meaning to text, these techniques produce a more structured analysis of textual knowledge than simple word searches, and can provide powerful tools for the production and analysis of systems biology models. PMID:17045684

  11. A Handy Interactive Class for Teaching Introductory Cell Biology

    Science.gov (United States)

    Hande, Shyamala

    2009-01-01

    In this paper we share the experience of an interactive method of teaching that involves every student in the learning process in the classroom. We describe an interactive class conducted over a two year period for premedical students. The process involved three stages namely a study session, a test-yourself session and a review session. Through…

  12. Developing Molecular Interaction Database and Searching for Similar Pathways (MOLECULAR BIOLOGY AND INFORMATION-Biological Information Science)

    OpenAIRE

    Kawashima, Shuichi; Katayama, Toshiaki; Kanehisa, Minoru

    1998-01-01

    We have developed a database named BRITE, which contains knowledge of interacting molecules and/or genes concering cell cycle and early development. Here, we report an overview of the database and the method of automatic search for functionally common sub-pathways between two biological pathways in BRITE.

  13. Aromatic-Aromatic Interactions in Biological System: Structure Activity Relationships

    Energy Technology Data Exchange (ETDEWEB)

    Rajagopal, Appavu; Deepa, Mohan [Molecular Biophysics Unit, Indian Institute of Sciences-Bangalore, Karnataka (India); Govindaraju, Munisamy [Bio-Spatial Technology Research Unit, Department of Environmental Biotechnology, School of Environmental Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu (India)

    2016-02-26

    While, intramolecular hydrogen bonds have attracted the greatest attention in studies of peptide conformations, the recognition that several other weakly polar interactions may be important determinants of folded structure has been growing. Burley and Petsko provided a comprehensive overview of the importance of weakly polar interactions, in shaping protein structures. The interactions between aromatic rings, which are spatially approximate, have attracted special attention. A survey of the proximal aromatic residue pairs in proteins, allowed Burley and Petsko to suggest that, “phenyl ring centroids are separated by a preferential distance of between 4.5 and 7 Å, and dihedral angles approximately 90° are most common”.

  14. Aromatic-Aromatic Interactions in Biological System: Structure Activity Relationships

    Directory of Open Access Journals (Sweden)

    Rajagopal Appavu

    2016-03-01

    Full Text Available While, intramolecular hydrogen bonds have attracted the greatest attention in studies of peptide conformations, the recognition that several other weakly polar interactions may be important determinants of folded structure has been growing. Burley and Petsko provided a comprehensive overview of the importance of weakly polar interactions, in shaping protein structures. The interactions between aromatic rings, which are spatially approximate, have attracted special attention. A survey of the proximal aromatic residue pairs in proteins, allowed Burley and Petsko to suggest that, “phenyl ring centroids are separated by a preferential distance of between 4.5 and 7 Å, and dihedral angles approximately 90° are most common”.

  15. Aromatic-Aromatic Interactions in Biological System: Structure Activity Relationships

    International Nuclear Information System (INIS)

    While, intramolecular hydrogen bonds have attracted the greatest attention in studies of peptide conformations, the recognition that several other weakly polar interactions may be important determinants of folded structure has been growing. Burley and Petsko provided a comprehensive overview of the importance of weakly polar interactions, in shaping protein structures. The interactions between aromatic rings, which are spatially approximate, have attracted special attention. A survey of the proximal aromatic residue pairs in proteins, allowed Burley and Petsko to suggest that, “phenyl ring centroids are separated by a preferential distance of between 4.5 and 7 Å, and dihedral angles approximately 90° are most common”

  16. Interaction Potential between Parabolic Rotator and an Outside Particle

    Directory of Open Access Journals (Sweden)

    Dan Wang

    2014-01-01

    Full Text Available At micro/nanoscale, the interaction potential between parabolic rotator and a particle located outside the rotator is studied on the basis of the negative exponential pair potential 1/Rn between particles. Similar to two-dimensional curved surfaces, we confirm that the potential of the three-dimensional parabolic rotator and outside particle can also be expressed as a unified form of curvatures; that is, it can be written as the function of curvatures. Furthermore, we verify that the driving forces acting on the particle may be induced by the highly curved micro/nano-parabolic rotator. Curvatures and the gradient of curvatures are the essential elements forming the driving forces. Through the idealized numerical experiments, the accuracy of the curvature-based potential is preliminarily proved.

  17. Cosmological solutions in string theory with dilaton self interaction potential

    CERN Document Server

    Mora, C

    2003-01-01

    In this work we present homogeneous and isotropic cosmological solutions for the low energy limit of string theory with a self interacting potential for the scalar field. For a potential that is a linear combination of two exponential, a family of exact solutions are found for the different spatial curvatures. Among this family a non singular accelerating solution for positive curvature is singled out and the violation of the energy conditions for that solution is studied, and also its astrophysical consequences. The string coupling for this solution is finite. (Author)

  18. Apoptotic cell clearance: basic biology and therapeutic potential.

    Science.gov (United States)

    Poon, Ivan K H; Lucas, Christopher D; Rossi, Adriano G; Ravichandran, Kodi S

    2014-03-01

    The prompt removal of apoptotic cells by phagocytes is important for maintaining tissue homeostasis. The molecular and cellular events that underpin apoptotic cell recognition and uptake, and the subsequent biological responses, are increasingly better defined. The detection and disposal of apoptotic cells generally promote an anti-inflammatory response at the tissue level, as well as immunological tolerance. Consequently, defects in apoptotic cell clearance have been linked with various inflammatory diseases and autoimmunity. Conversely, under certain conditions, such as the killing of tumour cells by specific cell-death inducers, the recognition of apoptotic tumour cells can promote an immunogenic response and antitumour immunity. Here, we review the current understanding of the complex process of apoptotic cell clearance in physiology and pathology, and discuss how this knowledge could be harnessed for new therapeutic strategies.

  19. The interaction time of a packet with a potential barrier

    International Nuclear Information System (INIS)

    They study the evolution of a wave packet impinging onto a one-dimensional potential barrier. The transmission and reflection times discussed in the literature for stationary states do not correspond to the times required for the emergence of a transmitted or a reflected packet. They propose new definitions for the interaction time and the transmission and reflection times which are suitable for packets and fit better the actual time evolution of the packet

  20. Comparing Extended System Interactions with Motions in Softened Potentials

    CERN Document Server

    Barnes, Eric I

    2015-01-01

    Using an $N$-body evolution code that does not rely on softened potentials, I have created a suite of interacting binary cluster simulations. The motions of the centers-of-mass of the clusters have been tracked and compared to the trajectories of point masses interacting via one of four different softened potential prescriptions. There is a robust, nearly linear relationship between the impact parameter of the cluster interaction and the point-mass softening length that best approximates the cluster centers-of-mass motion. In an $N$-body simulation that adopts a fixed softening length, such a relationship leads to regimes where two-body effects, like dynamical friction, can be either larger or smaller than the corresponding cluster situation. Further consideration of more specific $N$-body simulations leads to an estimate that roughly 10 per cent of point-mass interactions in an $N$-body simulation will experience two-body effects larger than those for equivalent clusters.

  1. POTENTIALS OF INTERACTIVE TEACHING TECHNIQUES TO TRAIN EXPERTS IN PHARMACY

    Directory of Open Access Journals (Sweden)

    A. V. Krikova

    2016-01-01

    Full Text Available Various interactive teaching methods and techniques are extensively used in modern higher schools. Their implementation is considered to be one of the most significant and efficient ways to improve quality of pharmaceutical professional training. Efficiency of these interactive techniques applied at the Department of Economics and Management of Pharmaceutical Business of Smolensk State Medical University has been comprehensively investigated and assessed. Obtained results are presented in the paper, as well as students’ survey data as consumers of educational services. Fifth year full-time students were involved into the study. Students’ awareness on potentials and significance of applied interactive teaching methods, as well as their interest in innovative forms to gain professional knowledge comprised 93.3%. Potentials of interactive techniques to teach students to deal with a diversity of real life practical professional tasks and problems are particularly emphasized in the study (86.7% students.

  2. Potential interaction and potential investigation of science center exhibits and visitors' interest

    Science.gov (United States)

    Busque, Laurier

    This research consisted of studying the characteristics of interaction and investigation potential present in museum or science center exhibits. Categories (strong and weak) for the characteristics of interaction potential and investigation potential were established. Fifteen exhibits were chosen from the Museum of Science (Ottawa) and from two science centers (Sudbury and Toronto); these were representative of the established characteristics and categories. A test was constructed that measured the interest in an exhibit in a museum or a science center. The final analysis of the test (20 items) reflects a coefficient of homogeneity (Cronbach alpha) of 0.97 (n = 278). In terms of the characteristics of interaction potential and investigation potential, a significant difference among the ranks of interest was not found once they were regrouped under the categories of strong and weak. The hypothesis of a relationship between the interaction potential and visitors' interest in an exhibit in a museum or science center and the hypothesis of a relationship between the investigation potential and the interest aroused were both rejected. In regards to the interaction potential, median ranks of interest in exhibits of 8.6 for the strong category and of 7.5 for the weak category were observed. In terms of the investigation potential, median ranks of interest of 7.0 for the strong category and of 9.1 for the weak category were observed. In the case of investigation potential, even if the difference is not significant, there is an indication that the strong investigation potential seems to have the effect of creating disinterest in the presentation of an exhibit in a museum or in a science center. In the context of new museum and science centers, the view of developing exhibits which are primarily objects which stimulate interest must be maintained. If this is done with exhibits that arc interactive and have an investigative approach, it is necessary for those in charge of

  3. Online Interactive Teaching Modules Enhance Quantitative Proficiency of Introductory Biology Students

    OpenAIRE

    Thompson, Katerina V.; Nelson, Kären C; Marbach-Ad, Gili; Keller, Michael; Fagan, William F.

    2010-01-01

    There is widespread agreement within the scientific and education communities that undergraduate biology curricula fall short in providing students with the quantitative and interdisciplinary problem-solving skills they need to obtain a deep understanding of biological phenomena and be prepared fully to contribute to future scientific inquiry. MathBench Biology Modules were designed to address these needs through a series of interactive, Web-based modules that can be used to supplement existi...

  4. Flavonoid-membrane interactions: possible consequences for biological effects of some polyphenolic compounds

    Institute of Scientific and Technical Information of China (English)

    Andrzej B HENDRICH

    2006-01-01

    Flavonoids are found ubiquitously in higher plants and constitute an important component of the majority of peoples' daily diets. The biological activities of flavonoids cover a very broad spectrum, from anticancer and antibacterial activities through to inhibition of bone resorption. In the present paper, the interactions between flavonoids and lipid bilayers as well as biological membranes and their components are reviewed, with special emphasis on the structure-activity relationships and mechanisms underlying the biological activity of flavonoids.

  5. Interaction of metallic clusters with biologically active curcumin molecules

    Science.gov (United States)

    Gupta, Sanjeev K.; He, Haiying; Liu, Chunhui; Dutta, Ranu; Pandey, Ravindra

    2015-09-01

    We have investigated the interaction of subnano metallic Gd and Au clusters with curcumin, an important biomolecule having pharmacological activity. Gd clusters show different site preference to curcumin and much stronger interaction strength, in support of the successful synthesis of highly stable curcumin-coated Gd nanoparticles as reported recently. It can be attributed to significant charge transfer from the Gd cluster to curcumin together with a relatively strong hybridization of the Gd df-orbitals with curcumin p-orbitals. These results suggest that Gd nanoparticles can effectively be used as delivery carriers for curcumin at the cellular level for therapy and medical imaging applications.

  6. A mirror code for protein-cholesterol interactions in the two leaflets of biological membranes.

    Science.gov (United States)

    Fantini, Jacques; Di Scala, Coralie; Evans, Luke S; Williamson, Philip T F; Barrantes, Francisco J

    2016-01-01

    Cholesterol controls the activity of a wide range of membrane receptors through specific interactions and identifying cholesterol recognition motifs is therefore critical for understanding signaling receptor function. The membrane-spanning domains of the paradigm neurotransmitter receptor for acetylcholine (AChR) display a series of cholesterol consensus domains (referred to as "CARC"). Here we use a combination of molecular modeling, lipid monolayer/mutational approaches and NMR spectroscopy to study the binding of cholesterol to a synthetic CARC peptide. The CARC-cholesterol interaction is of high affinity, lipid-specific, concentration-dependent, and sensitive to single-point mutations. The CARC motif is generally located in the outer membrane leaflet and its reverse sequence CRAC in the inner one. Their simultaneous presence within the same transmembrane domain obeys a "mirror code" controlling protein-cholesterol interactions in the outer and inner membrane leaflets. Deciphering this code enabled us to elaborate guidelines for the detection of cholesterol-binding motifs in any membrane protein. Several representative examples of neurotransmitter receptors and ABC transporters with the dual CARC/CRAC motifs are presented. The biological significance and potential clinical applications of the mirror code are discussed. PMID:26915987

  7. Communicative interactions improve visual detection of biological motion.

    Directory of Open Access Journals (Sweden)

    Valeria Manera

    Full Text Available BACKGROUND: In the context of interacting activities requiring close-body contact such as fighting or dancing, the actions of one agent can be used to predict the actions of the second agent. In the present study, we investigated whether interpersonal predictive coding extends to interactive activities--such as communicative interactions--in which no physical contingency is implied between the movements of the interacting individuals. METHODOLOGY/PRINCIPAL FINDINGS: Participants observed point-light displays of two agents (A and B performing separate actions. In the communicative condition, the action performed by agent B responded to a communicative gesture performed by agent A. In the individual condition, agent A's communicative action was substituted with a non-communicative action. Using a simultaneous masking detection task, we demonstrate that observing the communicative gesture performed by agent A enhanced visual discrimination of agent B. CONCLUSIONS/SIGNIFICANCE: Our finding complements and extends previous evidence for interpersonal predictive coding, suggesting that the communicative gestures of one agent can serve as a predictor for the expected actions of the respondent, even if no physical contact between agents is implied.

  8. Potential-of-mean-force description of ionic interactions and structural hydration in biomolecular systems

    Energy Technology Data Exchange (ETDEWEB)

    Hummer, G.; Garcia, A.E. [Los Alamos National Lab., NM (United States). Theoretical Biology and Biophysics Group; Soumpasis, D.M. [Max-Planck-Inst for Biophysical Chemistry, Goettingen (Germany). Biocomputation Group

    1994-10-01

    To understand the functioning of living organisms on a molecular level, it is crucial to dissect the intricate interplay of the immense number of biological molecules. Most of the biochemical processes in cells occur in a liquid environment formed mainly by water and ions. This solvent environment plays an important role in biological systems. The potential-of-mean-force (PMF) formalism attempts to describe quantitatively the interactions of the solvent with biological macromolecules on the basis of an approximate statistical-mechanical representation. At its current status of development, it deals with ionic effects on the biomolecular structure and with the structural hydration of biomolecules. The underlying idea of the PMF formalism is to identify the dominant sources of interactions and incorporate these interactions into the theoretical formalism using PMF`s (or particle correlation functions) extracted from bulk-liquid systems. In the following, the authors shall briefly outline the statistical-mechanical foundation of the PMF formalism and introduce the PMF expansion formalism, which is intimately linked to superposition approximations for higher-order particle correlation functions. The authors shall then sketch applications, which describe the effects of the ionic environment on nucleic-acid structure. Finally, the authors shall present the more recent extension of the PMF idea to describe quantitatively the structural hydration of biomolecules. Results for the interface of ice and water and for the hydration of deoxyribonucleic acid (DNA) will be discussed.

  9. The liver fluke Opisthorchis felineus: biology, epidemiology and carcinogenic potential.

    Science.gov (United States)

    Pakharukova, Mariya Y; Mordvinov, Viatcheslav A

    2016-01-01

    The liver fluke Opisthorchis felineus is a member of the triad of epidemiologically important liver fluke species belonging to the family Opisthorchiidae and the major agent causing opisthorchiasis over a vast territory, covering Russia, Kazakhstan and several European countries. The similarity between the diseases caused by O. felineus and other liver flukes, O. viverrini and Clonorchis sinensis, in clinical manifestations and course suggests that the scenarios of their development and, possibly, complications have much in common. The International Agency for Research on Cancer classified O. viverrini and C. sinensis as group 1 agents and the major factors inducing cholangiocarcinoma in endemic regions. However, a carcinogenic potential of O. felineus is poorly studied. This review characterizes O. felineus, briefs the epidemiological situation in Western Siberia, the world's largest opisthorchiasis focus, and assesses the carcinogenic potential of this liver fluke. The review is based on a comprehensive analysis of the published medical data on opisthorchiasis and its complications in Western Siberia. Results of performed analysis reflect the actual epidemiological situation in opisthorchiasis focus and suggest an association of this disease with bile duct cancer. PMID:26740360

  10. Mesenchymal stem cells: cell biology and potential use in therapy

    DEFF Research Database (Denmark)

    Kassem, Moustapha; Kristiansen, Malthe; Abdallah, Basem M

    2004-01-01

    Mesenchymal stem cells are clonogenic, non-haematopoietic stem cells present in the bone marrow and are able to differentiate into multiple mesoderm-type cell lineages e.g. osteoblasts, chondrocytes, endothelial-cells and also non-mesoderm-type lineages e.g. neuronal-like cells. Several methods...... are currently available for isolation of the mesenchymal stem cells based on their physical and immunological characteristics. Because of the ease of their isolation and their extensive differentiation potential, mesenchymal stem cells are among the first stem cell types to be introduced in the clinic. Recent...... studies have demonstrated that the life span of mesenchymal stem cells in vitro can be extended by increasing the levels of telomerase expression in the cells and thus allowing culture of large number of cells needed for therapy. In addition, it has been shown that it is possible to culture the cells...

  11. Variance heterogeneity analysis for detection of potentially interacting genetic loci: method and its limitations

    Directory of Open Access Journals (Sweden)

    van Duijn Cornelia

    2010-10-01

    Full Text Available Abstract Background Presence of interaction between a genotype and certain factor in determination of a trait's value, it is expected that the trait's variance is increased in the group of subjects having this genotype. Thus, test of heterogeneity of variances can be used as a test to screen for potentially interacting single-nucleotide polymorphisms (SNPs. In this work, we evaluated statistical properties of variance heterogeneity analysis in respect to the detection of potentially interacting SNPs in a case when an interaction variable is unknown. Results Through simulations, we investigated type I error for Bartlett's test, Bartlett's test with prior rank transformation of a trait to normality, and Levene's test for different genetic models. Additionally, we derived an analytical expression for power estimation. We showed that Bartlett's test has acceptable type I error in the case of trait following a normal distribution, whereas Levene's test kept nominal Type I error under all scenarios investigated. For the power of variance homogeneity test, we showed (as opposed to the power of direct test which uses information about known interacting factor that, given the same interaction effect, the power can vary widely depending on the non-estimable direct effect of the unobserved interacting variable. Thus, for a given interaction effect, only very wide limits of power of the variance homogeneity test can be estimated. Also we applied Levene's approach to test genome-wide homogeneity of variances of the C-reactive protein in the Rotterdam Study population (n = 5959. In this analysis, we replicate previous results of Pare and colleagues (2010 for the SNP rs12753193 (n = 21, 799. Conclusions Screening for differences in variances among genotypes of a SNP is a promising approach as a number of biologically interesting models may lead to the heterogeneity of variances. However, it should be kept in mind that the absence of variance heterogeneity for

  12. Modular Verification of Interactive Systems with an Application to Biology

    Directory of Open Access Journals (Sweden)

    P. Milazzo

    2011-01-01

    Full Text Available We propose sync-programs, an automata-based formalism for the description of biological systems, and a modular verification technique for such a formalism that allows properties expressed in the universal fragment of CTL to be verified on suitably chosen fragments of models, rather than on whole models. As an application we show the modelling of the lac operon regulation process and the modular verification of some properties. Verification of properties is performed by using the NuSMV model checker and we show that by applying our modular verification technique we can verify properties in shorter times than those necessary to verify the same properties in the whole model.

  13. Systems Biology of Platelet-Vessel Wall Interactions.

    Directory of Open Access Journals (Sweden)

    Scott L. Diamond

    2013-08-01

    Full Text Available Blood Systems Biology seeks to quantify outside-in signaling as platelets respond to numerous external stimuli, typically under flow conditions. Platelets can activate via GPVI collagen receptor and numerous G-protein coupled receptors (GPCRs responsive to ADP, thromboxane, thrombin, and prostacyclin. A bottom-up ODE approach allowed prediction of platelet calcium and phosphoinositides following P2Y1 activation with ADP, either for a population average or single cell stochastic behavior. The homeostasis assumption (i.e. a resting platelet stays resting until activated was particularly useful in finding global steady states for these large metabolic networks. Alternatively, a top-down approach involving Pairwise Agonist Scanning allowed large data sets of measured calcium mobilization to predict an individual’s platelet responses. The data was used to train Neural Network (NN models of signaling to predict patient-specific responses to combinatorial stimulation. A kinetic description of platelet signaling then allows prediction of inside-out activation of platelets as they experience the complex biochemical milieu at the site of thrombosis. Multiscale lattice kinetic Monte Carlo (LKMC utilizes these detailed descriptions of platelet signaling under flow conditions where released soluble species are solved by finite element method and the flow field around the growing thrombus is updated using computational fluid dynamics or lattice Boltzmann method. Since hemodynamic effects are included in a multiscale approach, thrombosis can then be predicted under arterial and venous thrombotic conditions for various anatomical geometries. Such systems biology approaches accommodate the effect of anti-platelet pharmacological intervention where COX1 pathways or ADP signaling are modulated in a patient-specific manner.

  14. Quantifying electron transfer reactions in biological systems: what interactions play the major role?

    Science.gov (United States)

    Sjulstok, Emil; Olsen, Jógvan Magnus Haugaard; Solov'Yov, Ilia A.

    2015-12-01

    Various biological processes involve the conversion of energy into forms that are usable for chemical transformations and are quantum mechanical in nature. Such processes involve light absorption, excited electronic states formation, excitation energy transfer, electrons and protons tunnelling which for example occur in photosynthesis, cellular respiration, DNA repair, and possibly magnetic field sensing. Quantum biology uses computation to model biological interactions in light of quantum mechanical effects and has primarily developed over the past decade as a result of convergence between quantum physics and biology. In this paper we consider electron transfer in biological processes, from a theoretical view-point; namely in terms of quantum mechanical and semi-classical models. We systematically characterize the interactions between the moving electron and its biological environment to deduce the driving force for the electron transfer reaction and to establish those interactions that play the major role in propelling the electron. The suggested approach is seen as a general recipe to treat electron transfer events in biological systems computationally, and we utilize it to describe specifically the electron transfer reactions in Arabidopsis thaliana cryptochrome-a signaling photoreceptor protein that became attractive recently due to its possible function as a biological magnetoreceptor.

  15. Encoding the states of interacting proteins to facilitate biological pathways reconstruction

    Directory of Open Access Journals (Sweden)

    Termanini Alberto

    2010-08-01

    Full Text Available Abstract Background In a systems biology perspective, protein-protein interactions (PPI are encoded in machine-readable formats to avoid issues encountered in their retrieval for the reconstruction of comprehensive interaction maps and biological pathways. However, the information stored in electronic formats currently used doesn't allow a valid automatic reconstruction of biological pathways. Results We propose a logical model of PPI that takes into account the "state" of proteins before and after the interaction. This information is necessary for proper reconstruction of the pathway. Conclusions The adoption of the proposed model, which can be easily integrated into existing machine-readable formats used to store the PPI data, would facilitate the automatic or semi-automated reconstruction of biological pathways. Reviewers This article was reviewed by Dr. Wen-Yu Chung (nominated by Kateryna Makova, Dr. Carl Herrmann (nominated by Dr. Purificación López-García and Dr. Arcady Mushegian.

  16. Gender differences, polypharmacy, and potential pharmacological interactions in the elderly

    Directory of Open Access Journals (Sweden)

    Carina Duarte Venturini

    2011-01-01

    Full Text Available OBJECTIVE: This study aims to analyze pharmacological interactions among drugs taken by elderly patients and their age and gender differences in a population from Porto Alegre, Brazil. METHODS: We retrospectively analyzed the database provided by the Institute of Geriatric and Gerontology, Porto Alegre, Brazil. The database was composed of 438 elderly and includes information about the patients' disease, therapy regimens, utilized drugs. All drugs reported by the elderly patients were classified using the Anatomical Therapeutic and Chemical Classification System. The drug-drug interactions and their severity were assessed using the Micromedex® Healthcare Series. RESULTS: Of the 438 elderly patients in the data base, 376 (85.8% used pharmacotherapy, 274 were female, and 90.4% of females used drugs. The average number of drugs used by each individual younger than 80 years was 3.2±2.6. Women younger than 80 years old used more drugs than men in the same age group whereas men older than 80 years increased their use of drugs in relation to other age groups. Therefore, 32.6% of men and 49.2% of women described at least one interaction, and 8.1% of men and 10.6% of women described four or more potential drug-drug interactions. Two-thirds of drug-drug interactions were moderate in both genders, and most of them involved angiotensin-converting enzyme inhibitor, non-steroidal anti-inflammatory, loop and thiazide diuretics, and β-blockers. CONCLUSION: Elderly patients should be closely monitored, based on drug class, gender, age group and nutritional status.

  17. Microscopic positive-energy potential based on Gogny interaction

    CERN Document Server

    Blanchon, G; Arellano, H F; Mau, N Vinh

    2014-01-01

    We present nucleon elastic scattering calculation based on Green's function formalism in the Random-Phase Approximation. For the first time, the Gogny effective interaction is used consistently throughout the whole calculation to account for the complex, non-local and energy-dependent optical potential. Effects of intermediate single-particle resonances are included and found to play a crucial role in the account for measured reaction cross section. Double counting of the particle-hole second-order contribution is carefully addressed. The resulting integro-differential Schr\\"odinger equation for the scattering process is solved without localization procedures. The method is applied to neutron and proton elastic scattering from $^{40}$Ca. A successful account for differential and integral cross sections, including analyzing powers, is obtained for incident energies up to 30 MeV. Discrepancies at higher energies are related to much too high volume integral of the real potential for large partial waves. Moreover...

  18. Dynamics of elastic interactions in soft and biological matter

    Science.gov (United States)

    Yuval, Janni; Safran, Samuel A.

    2013-04-01

    Cells probe their mechanical environment and can change the organization of their cytoskeletons when the elastic and viscous properties of their environment are modified. We use a model in which the forces exerted by small, contractile acto-myosin filaments (e.g., nascent stress fibers in stem cells) on the extracellular matrix are modeled as local force dipoles. In some cases, the strain field caused by these force dipoles propagates quickly enough so that only static elastic interactions need be considered. On the other hand, in the case of significant energy dissipation, strain propagation is slower and may be eliminated completely by the relaxation of the cellular cytoskeleton (e.g., by cross-link dissociation). Here, we consider several dissipative mechanisms that affect the propagation of the strain field in adhered cells and consider these effects on the interaction between force dipoles and their resulting mutual orientations. This is a first step in understanding the development of orientational (nematic) or layering (smectic) order in the cytoskeleton. We use the theory to estimate the propagation time of the strain fields over a cellular distance for different mechanisms and find that in some cases it can be of the order of seconds, thus competing with the cytoskeletal relaxation time. Furthermore, for a simple system of two force dipoles, we predict that in some cases the orientation of force dipoles might change significantly with time, e.g., for short times the dipoles exhibit parallel alignment while for later times they align perpendicularly.

  19. Electron spin interactions in chemistry and biology fundamentals, methods, reactions mechanisms, magnetic phenomena, structure investigation

    CERN Document Server

    Likhtenshtein, Gertz

    2016-01-01

    This book presents the versatile and pivotal role of electron spin interactions in nature. It provides the background, methodologies and tools for basic areas related to spin interactions, such as spin chemistry and biology, electron transfer, light energy conversion, photochemistry, radical reactions, magneto-chemistry and magneto-biology. The book also includes an overview of designing advanced magnetic materials, optical and spintronic devices and photo catalysts. This monograph appeals to scientists and graduate students working in the areas related to spin interactions physics, biophysics, chemistry and chemical engineering.

  20. [Evaluation of biological and clinical potential of paleolithic diet].

    Science.gov (United States)

    Kowalski, Lukasz M; Bujko, Jacek

    2012-01-01

    Accumulating evidences suggest that foods that were regularly consumed during the human primates and evolution, in particular during the Paleolithic era (2.6-0.01 x 10(6) years ago), may be optimal for the prevention and treatment of some chronic diseases. It has been postulated that fundamental changes in the diet and other lifestyle conditions that occurred after the Neolithic Revolution, and more recently with the beginning of the Industrial Revolution are too recent taking into account the evolutionary time scale for the human genome to have completely adjust. In contemporary Western populations at least 70% of daily energy intake is provided by foods that were rarely or never consumed by Paleolithic hunter-gatherers, including grains, dairy products as well as refined sugars and highly processed fats. Additionally, compared with Western diets, Paleolithic diets, based on recently published estimates of macronutrient and fatty acid intakes from an East African Paleolithic diet, contained more proteins and long-chain polyunsaturated fatty acids, and less linoleic acid. Observational studies of hunter-gatherers and other non-western populations lend support to the notion that a Paleolithic type diet may reduce the risk of cardiovascular disease, metabolic syndrome, type 2 diabetes, cancer, acne vulgaris and myopia. Moreover, preliminary intervention studies using contemporary diet based on Paleolithic food groups (meat, fish, shellfish, fresh fruits and vegetables, roots, tubers, eggs, and nuts), revealed promising results including favorable changes in risk factors, such as weight, waist circumference, C-reactive protein, glycated haemoglobin (HbAlc), blood pressure, glucose tolerance, insulin secretion, insulin sensitivity and lipid profiles. Low calcium intake, which is often considered as a potential disadvantage of the Paleolithic diet model, should be weighed against the low content of phytates and the low content of sodium chloride, as well as the high

  1. Potential for widespread application of biological control of stored-product pests

    DEFF Research Database (Denmark)

    Hansen, Lise Stengaard

    2007-01-01

    Biological control of stored product pests has substantial potential in Europe". This is essentially the conclusion of the activities of a European working group funded by the COST system, an intergovernmental networking system. Working group 4 of COST action 842 (2000-2005) focussed on biological...... control of stored-product pests and has considered a number of existing and potential fields for application of biological control. Three situations were identified where biological control would be a valuable component of integrated pest management: (1) Empty room treatment against stored-product mites......, beetles and moths; (2) Preventative treatment of bulk commodities against weevils (Sitophilus spp.) and storage mites; (3) Preventative application of egg-parasitoids against moths in packaged products. Development of methods for biological control and of mass production of natural enemies...

  2. The relevance and potential roles of microphysiological systems in biology and medicine

    OpenAIRE

    Wikswo, John P.

    2014-01-01

    Microphysiological systems (MPS), consisting of interacting organs-on-chips or tissue-engineered, 3D organ constructs that use human cells, present an opportunity to bring new tools to biology, medicine, pharmacology, physiology, and toxicology. This issue of Experimental Biology and Medicine describes the ongoing development of MPS that can serve as in vitro models for bone and cartilage, brain, gastrointestinal tract, lung, liver, microvasculature, reproductive tract, skeletal muscle, and s...

  3. Potential interaction between proton pump inhibitor and clopidogrel

    Directory of Open Access Journals (Sweden)

    Indra Kurniawan

    2013-02-01

    Full Text Available Clopidogrel is an anti-platelet agent commonly used in patients with atherosclerotic cardiovascular (CV disease. Although formerly considered safe, several studies reported that the use of clopidogrel may cause a significant increase in the rate of gastrointestinal (GI bleeding. This adverse effect could be minimized by coadministration of proton pump inhibitor (PPI. However, since PPI and clopidogrel share the same metabolic pathway, it has been hypothesized that the administration of PPI following clopidogrel therapy may cause a reduction in its anti-platelet effect, thereby increasing the risk of CV events. Recent studies found no significant inhibition in the activation of clopidogrel by CYP2C19 with administration of PPI in vitro. Pharmacokinetic and pharmacodynamic studies, as well as clinical studies, reported conflicting results regarding the potential interaction between PPI and clopidogrel. Until now, the available study investigated the PPI-clopidogrel interaction are primarily observational. The COGENT study is the only prospective, placebo-controlled trial examined the PPI-clopidogrel interaction. This study revealed no significant increase in CV events in patients receiving PPI following clopidogrel therapy, compared to the control group. Though remains controversial, current expert consensus recommended the administration of PPI in patients receiving clopidogrel, particularly in high-risk patients. (Med J Indones. 2013;22:57-62Keywords: Cardiovascular, clopidogrel, gastrointestinal, proton pump inhibitor

  4. Potentials of single-cell biology in identification and validation of disease biomarkers.

    Science.gov (United States)

    Niu, Furong; Wang, Diane C; Lu, Jiapei; Wu, Wei; Wang, Xiangdong

    2016-09-01

    Single-cell biology is considered a new approach to identify and validate disease-specific biomarkers. However, the concern raised by clinicians is how to apply single-cell measurements for clinical practice, translate the message of single-cell systems biology into clinical phenotype or explain alterations of single-cell gene sequencing and function in patient response to therapies. This study is to address the importance and necessity of single-cell gene sequencing in the identification and development of disease-specific biomarkers, the definition and significance of single-cell biology and single-cell systems biology in the understanding of single-cell full picture, the development and establishment of whole-cell models in the validation of targeted biological function and the figure and meaning of single-molecule imaging in single cell to trace intra-single-cell molecule expression, signal, interaction and location. We headline the important role of single-cell biology in the discovery and development of disease-specific biomarkers with a special emphasis on understanding single-cell biological functions, e.g. mechanical phenotypes, single-cell biology, heterogeneity and organization of genome function. We have reason to believe that such multi-dimensional, multi-layer, multi-crossing and stereoscopic single-cell biology definitely benefits the discovery and development of disease-specific biomarkers.

  5. A new methodology for studying nanoparticle interactions in biological systems: Dispersing titania in biocompatible media using chemical stabilisers

    Science.gov (United States)

    Ramirez-Garcia, Sonia; Chen, Lan; Morris, Michael A.; Dawson, Kenneth A.

    2011-11-01

    We report here a highly successful and original protocol for the dispersion of nanoparticles in biocompatible fluids for in vitro and in vivo studies of the nanoparticle-biology interaction. Titania is chosen as a suitable model as it is one of the priority materials listed by the OECD and small particles of the anatase structure are extensively used as e.g. photocatalysts in solar cells. Consequently, its delivery into the environment and its interaction with biological organisms is unavoidable. Therefore, its biological effect needs to be understood. In this work, we prepared stable nanoparticle dispersions of anatase aggregates using citrate stabilisations between 45 and 55 nm at concentrations of up to 10 mg mL-1. The optimum pH for this type of suspension was 7, resulting in ζ-potentials of approximately -50 mV. The stabilised aggregates were the subject of dialysis to produce stable dispersions without the chemical stabiliser, thus allowing studies in the absence of potentially toxic chemicals. Different sizing techniques such as Dynamic Light Scattering (DLS), Nanoparticle Tracking Analysis (NTA) and Differential Centrifuge Sedimentation (DCS) were used to characterise the different suspensions. The results obtained with each of these techniques are compared and a critical analysis of the suitability of each technique is given.We report here a highly successful and original protocol for the dispersion of nanoparticles in biocompatible fluids for in vitro and in vivo studies of the nanoparticle-biology interaction. Titania is chosen as a suitable model as it is one of the priority materials listed by the OECD and small particles of the anatase structure are extensively used as e.g. photocatalysts in solar cells. Consequently, its delivery into the environment and its interaction with biological organisms is unavoidable. Therefore, its biological effect needs to be understood. In this work, we prepared stable nanoparticle dispersions of anatase aggregates

  6. Hyperfine interaction measurements in biological compounds: the case of hydroxyapatite

    International Nuclear Information System (INIS)

    The use o nanoparticles in current medicine are under intense investigation. The possible advantages proposed by these systems are very impressive and the results may be quite schemer. In this scenario, the association of nanoparticles with radioactive materials (radionuclide) may be the most important step since the discovery of radioactive for nuclear medicine and radiopharmacy, especially for cancer targeting and therapy. The hyperfine interaction of the nuclear probe 111Cd in the Hydroxyapatite compounds has been investigated by perturbed angular correlation (PAC) spectroscopy in room temperature for the hydroxyapatite made in the temperatures of 90°C, 35°C and with Ho doped, both thermalized and not. The thermalized samples were heated to T= 1273 K for 6 h. The 111Cd was broadcast in the structure of the material by diffusion, closing in quartz tubes were heated – together with the radioactive PAC probe 111In/111Cd to T = 1073 K for 12 h. In not thermalized samples the PAC spectra indicate a distribution of frequency, but in the thermalized samples, the PAC spectra shows the presence of β-tri calcium phosphate in the structure of this kind of Hydroxyapatite. (author)

  7. BioGRID: A Resource for Studying Biological Interactions in Yeast.

    Science.gov (United States)

    Oughtred, Rose; Chatr-aryamontri, Andrew; Breitkreutz, Bobby-Joe; Chang, Christie S; Rust, Jennifer M; Theesfeld, Chandra L; Heinicke, Sven; Breitkreutz, Ashton; Chen, Daici; Hirschman, Jodi; Kolas, Nadine; Livstone, Michael S; Nixon, Julie; O'Donnell, Lara; Ramage, Lindsay; Winter, Andrew; Reguly, Teresa; Sellam, Adnane; Stark, Chris; Boucher, Lorrie; Dolinski, Kara; Tyers, Mike

    2016-01-01

    The Biological General Repository for Interaction Datasets (BioGRID) is a freely available public database that provides the biological and biomedical research communities with curated protein and genetic interaction data. Structured experimental evidence codes, an intuitive search interface, and visualization tools enable the discovery of individual gene, protein, or biological network function. BioGRID houses interaction data for the major model organism species--including yeast, nematode, fly, zebrafish, mouse, and human--with particular emphasis on the budding yeast Saccharomyces cerevisiae and the fission yeast Schizosaccharomyces pombe as pioneer eukaryotic models for network biology. BioGRID has achieved comprehensive curation coverage of the entire literature for these two major yeast models, which is actively maintained through monthly curation updates. As of September 2015, BioGRID houses approximately 335,400 biological interactions for budding yeast and approximately 67,800 interactions for fission yeast. BioGRID also supports an integrated posttranslational modification (PTM) viewer that incorporates more than 20,100 yeast phosphorylation sites curated through its sister database, the PhosphoGRID. PMID:26729913

  8. Recent Developments in Systems Biology and Metabolic Engineering of Plant–Microbe Interactions

    Science.gov (United States)

    Kumar, Vishal; Baweja, Mehak; Singh, Puneet K.; Shukla, Pratyoosh

    2016-01-01

    Microorganisms play a crucial role in the sustainability of the various ecosystems. The characterization of various interactions between microorganisms and other biotic factors is a necessary footstep to understand the association and functions of microbial communities. Among the different microbial interactions in an ecosystem, plant–microbe interaction plays an important role to balance the ecosystem. The present review explores plant–microbe interactions using gene editing and system biology tools toward the comprehension in improvement of plant traits. Further, system biology tools like FBA (flux balance analysis), OptKnock, and constraint-based modeling helps in understanding such interactions as a whole. In addition, various gene editing tools have been summarized and a strategy has been hypothesized for the development of disease free plants. Furthermore, we have tried to summarize the predictions through data retrieved from various types of sources such as high throughput sequencing data (e.g., single nucleotide polymorphism detection, RNA-seq, proteomics) and metabolic models have been reconstructed from such sequences for species communities. It is well known fact that systems biology approaches and modeling of biological networks will enable us to learn the insight of such network and will also help further in understanding these interactions. PMID:27725824

  9. Research on the potential use of interactive materials on astronomy education

    Science.gov (United States)

    Voelzke, Marcos Rincon; Macedo, Josue

    2016-07-01

    This study presents results of a survey conducted at the Federal Institution of Education, Science and Technology in the North of Minas Gerais (IFNMG), and aimed to investigate the potentialities of the use of interactive materials in the teaching of astronomy. An advanced training course with involved learning activities about basic concepts of astronomy was offered to thirty-two Licenciate students in Physics, Mathematics and Biological Sciences, using the mixed methodology, combined with the three pedagogical moments. Among other aspects, the viability of the use of resources was noticed, involving digital technologies and interactive materials on teaching of astronomy, which may contribute to the broadening of methodological options for future teachers and meet their training needs.

  10. Arsenic: A Review of the Element's Toxicity, Plant Interactions, and Potential Methods of Remediation.

    Science.gov (United States)

    Hettick, Bryan E; Cañas-Carrell, Jaclyn E; French, Amanda D; Klein, David M

    2015-08-19

    Arsenic is a naturally occurring element with a long history of toxicity. Sites of contamination are found worldwide as a result of both natural processes and anthropogenic activities. The broad scope of arsenic toxicity to humans and its unique interaction with the environment have led to extensive research into its physicochemical properties and toxic behavior in biological systems. The purpose of this review is to compile the results of recent studies concerning the metalloid and consider the chemical and physical properties of arsenic in the broad context of human toxicity and phytoremediation. Areas of focus include arsenic's mechanisms of human toxicity, interaction with plant systems, potential methods of remediation, and protocols for the determination of metals in experimentation. This assessment of the literature indicates that controlling contamination of water sources and plants through effective remediation and management is essential to successfully addressing the problems of arsenic toxicity and contamination.

  11. Schematic potential energy for interaction between isobutene and zeolite mordenite

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Serrano, L A [Programa de Crudo Maya, IMP, AP 15-805, DF 07730 (Mexico); Flores-Sandoval, C A [Programa de Crudo Maya, IMP, AP 15-805, DF 07730 (Mexico); Zaragoza, I P [Programa de Ingenieria Molecular, IMP, AP 15-805, DF 07730 (Mexico)

    2004-06-09

    A schematic representation of the potential energy for the interaction between isobutene and H mordenite was presented by using eight different positions (P1-P8) of C{sub 1} or C{sub 2} atoms located in front of the acid hydrogen (H{sup +}). In all cases a {pi} complex was formed yielding different values of the adsorption energy. In some cases of the adsorption point in P1-P8 the frontier orbitals are shown. The P8 position exhibits the highest value obtained for the adsorption energy, where the C{sub 1} atom is in front of the H{sup +}. Calculations were of all electron type employing HF/6-31G**.

  12. Multi-scale Observation of Biological Interactions of Nanocarriers: from Nano to Macro

    OpenAIRE

    Jin, Su-Eon; Bae, Jin Woo; Hong, Seungpyo

    2010-01-01

    Microscopic observations have played a key role in recent advancements in nanotechnology-based biomedical sciences. In particular, multi-scale observation is necessary to fully understand the nano-bio interfaces where a large amount of unprecedented phenomena have been reported. This review describes how to address the physicochemical and biological interactions of nanocarriers within the biological environments using microscopic tools. The imaging techniques are categorized based on the size...

  13. Interactions among endophytic bacteria and fungi: effects and potentials

    Indian Academy of Sciences (India)

    W M M S Bandara; Gamini Seneviratne; S A Kulasooriya

    2006-12-01

    Plants benefit extensively by harbouring endophytic microbes. They promote plant growth and confer enhanced resistance to various pathogens. However, the way the interactions among endophytes influence the plant productivity has not been explained. Present study experimentally showed that endophytes isolated from rice (Oryza sativa) used as the test plant produced two types of interactions; biofilms (bacteria attached to mycelia) and mixed cultures with no such attachments. Acidity, as measured by pH in cultures with biofilms was higher than that of fungi alone, bacteria alone or the mixed cultures. Production of indoleacetic acid like substances (IAAS) of biofilms was higher than that of mixed cultures, fungi or bacteria. Bacteria and fungi produced higher quantities of IAAS than mixed cultures. In mixed cultures, the potential of IAAS production of resident microbes was reduced considerably. There was a negative relationship between IAAS and pH of the biofilms, indicating that IAAS was the main contributor to the acidity. However, such a relationship was not observed in mixed cultures. Microbial acid production is important for suppressing plant pathogens. Thus the biofilm formation in endophytic environment seems to be very important for healthy and improved plant growth. However, it is unlikely that an interaction among endophytes takes place naturally in the endophytic environment, due to physical barriers of plant tissues. Further, critical cell density dependant quorum sensing that leads to biofilm formation may not occur in the endophytic environment as there is a limited space. As such in vitro production and application of beneficial biofilmed inocula of endophytes are important for improved plant production in any agro-ecosystem. The conventional practice of plant inoculation with monocultures or mixed cultures of effective microbes may not give the highest microbial effect, which may only be achieved by biofilm formation.

  14. The Potential Use of Indigobush (Amorpha fruticosa L.) as Natural Resource of Biologically Active Compounds

    OpenAIRE

    Tamara Jakovljević; Jasna Halambek; Kristina Radošević; Karla Hanousek; Marija Gradečki-Poštenjak; Višnja Gaurina Srček; Ivana Radojčić Redovniković; Alessandra De Marco

    2015-01-01

    Background and Purpose: Recent research indicates that a weed like Indigobush (Amorpha fruticosa L.) gives great opportunities for its commercialization through a rich spectrum of its beneficial biological features with possible use in the forestry and biotechnology field. Therefore, in this study we wanted to explore some of potential application of Indigobush extract, as a source of biologically active compounds, for animal cell culturing as well as green corrosion inhibitors. Materials ...

  15. Kinetic limits for pair-interaction driven master equations and biological swarm models

    CERN Document Server

    Carlen, Eric; Wennberg, Bernt

    2011-01-01

    We consider a class of stochastic processes modeling binary interactions in an N-particle system. Examples of such systems can be found in the modeling of biological swarms. They lead to the definition of a class of master equations that we call pair interaction driven master equations. We prove a propagation of chaos result for this class of master equations which generalizes Mark Kac's well know result for the Kac model in kinetic theory. We use this result to study kinetic limits for two biological swarm models. We show that propagation of chaos may be lost at large times and we exhibit an example where the invariant density is not chaotic.

  16. Probability-based model of protein-protein interactions on biological timescales

    Directory of Open Access Journals (Sweden)

    Bates Paul A

    2006-12-01

    Full Text Available Abstract Background Simulation methods can assist in describing and understanding complex networks of interacting proteins, providing fresh insights into the function and regulation of biological systems. Recent studies have investigated such processes by explicitly modelling the diffusion and interactions of individual molecules. In these approaches, two entities are considered to have interacted if they come within a set cutoff distance of each other. Results In this study, a new model of bimolecular interactions is presented that uses a simple, probability-based description of the reaction process. This description is well-suited to simulations on timescales relevant to biological systems (from seconds to hours, and provides an alternative to the previous description given by Smoluchowski. In the present approach (TFB the diffusion process is explicitly taken into account in generating the probability that two freely diffusing chemical entities will interact within a given time interval. It is compared to the Smoluchowski method, as modified by Andrews and Bray (AB. Conclusion When implemented, the AB & TFB methods give equivalent results in a variety of situations relevant to biology. Overall, the Smoluchowski method as modified by Andrews and Bray emerges as the most simple, robust and efficient method for simulating biological diffusion-reaction processes currently available.

  17. The evolution of early cellular systems viewed through the lens of biological interactions

    Directory of Open Access Journals (Sweden)

    Anthony M Poole

    2015-10-01

    Full Text Available The minimal cell concept represents a pragmatic approach to the question of how few genes are required to run a cell. This is a helpful way to build a parts-list, and has been more successful than attempts to deduce a minimal gene set for life by inferring the gene repertoire of the Last Universal Common Ancestor, as few genes trace back to this hypothetical ancestral state. However, the study of minimal cellular systems is the study of biological outliers where, by practical necessity, coevolutionary interactions are minimised or ignored. In this paper, we consider the biological context from which minimal genomes have been removed. For instance, some of the most reduced genomes are from endosymbionts and are the result of coevolutionary interactions with a host; few such organisms are ‘free-living’. As few, if any, biological systems exist in complete isolation, we expect that, as with modern life, early biological systems were part of an ecosystem, replete with organismal interactions. We favour refocusing discussions of the evolution of cellular systems on processes rather than gene counts. We therefore draw a distinction between a pragmatic minimal cell (an interesting engineering problem, a distributed genome (a system resulting from an evolutionary transition involving more than one cell and the looser coevolutionary interactions that are ubiquitous in ecosystems. Finally, we consider the distributed genome and coevolutionary interactions between genomic entities in the context of early evolution.

  18. Asymptotic near-nucleus structure of the electron-interaction potential in local effective potential theories

    International Nuclear Information System (INIS)

    In local effective potential theories of electronic structure, the electron correlations due to the Pauli exclusion principle, Coulomb repulsion, and correlation-kinetic effects, are all incorporated in the local electron-interaction potential vee(r). In previous work, it has been shown that for spherically symmetric or sphericalized systems, the asymptotic near-nucleus expansion of this potential is vee(r)=vee(0)+βr+O(r2), with vee(0) being finite. By assuming that the Schroedinger and local effective potential theory wave functions are analytic near the nucleus of atoms, we prove the following via quantal density functional theory (QDFT): (i) Correlations due to the Pauli principle and Coulomb correlations do not contribute to the linear structure; (ii) these Pauli and Coulomb correlations contribute quadratically; (iii) the linear structure is solely due to correlation-kinetic effects, the contributions of these effects being determined analytically. We also derive by application of adiabatic coupling constant perturbation theory via QDFT (iv) the asymptotic near-nucleus expansion of the Hohenberg-Kohn-Sham theory exchange vx(r) and correlation vc(r) potentials. These functions also approach the nucleus linearly with the linear term of vx(r) being solely due to the lowest-order correlation kinetic effects, and the linear term of vc(r) being due solely to the higher-order correlation kinetic contributions. The above conclusions are equally valid for systems of arbitrary symmetry, provided spherical averages of the properties are employed

  19. Revealing complex function, process and pathway interactions with high-throughput expression and biological annotation data.

    Science.gov (United States)

    Singh, Nitesh Kumar; Ernst, Mathias; Liebscher, Volkmar; Fuellen, Georg; Taher, Leila

    2016-10-20

    The biological relationships both between and within the functions, processes and pathways that operate within complex biological systems are only poorly characterized, making the interpretation of large scale gene expression datasets extremely challenging. Here, we present an approach that integrates gene expression and biological annotation data to identify and describe the interactions between biological functions, processes and pathways that govern a phenotype of interest. The product is a global, interconnected network, not of genes but of functions, processes and pathways, that represents the biological relationships within the system. We validated our approach on two high-throughput expression datasets describing organismal and organ development. Our findings are well supported by the available literature, confirming that developmental processes and apoptosis play key roles in cell differentiation. Furthermore, our results suggest that processes related to pluripotency and lineage commitment, which are known to be critical for development, interact mainly indirectly, through genes implicated in more general biological processes. Moreover, we provide evidence that supports the relevance of cell spatial organization in the developing liver for proper liver function. Our strategy can be viewed as an abstraction that is useful to interpret high-throughput data and devise further experiments.

  20. On the mechanisms of interaction of low-intensity millimeter waves with biological objects

    Science.gov (United States)

    Betskii, O. V.

    1994-01-01

    The interaction of low-intensity millimeter-band electromagnetic waves with biological objects is examined. These waves are widely used in medical practice as a means of physiotherapy for the treatment of various human disorders. Principal attention is given to the mechanisms through which millimeter waves act on the human organism.

  1. Low-level radiation: biological interactions, risks, and benefits. A bibliography

    International Nuclear Information System (INIS)

    The bibliography contains 3294 references that were selected from the Department of Energy's data base (EDB). The subjects covered are lower-level radiation effects on man, environmental radiation, and other biological interactions of radiation that appear to be applicable to the low-level radiation problem

  2. Low-level radiation: biological interactions, risks, and benefits. A bibliography

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-09-01

    The bibliography contains 3294 references that were selected from the Department of Energy's data base (EDB). The subjects covered are lower-level radiation effects on man, environmental radiation, and other biological interactions of radiation that appear to be applicable to the low-level radiation problem.

  3. On the mechanisms of interaction of low-intensity millimeter waves with biological objects

    Energy Technology Data Exchange (ETDEWEB)

    Betskii, O.V.

    1994-07-01

    The interaction of low-intensity millimeter-band electromagnetic waves with biological objects is examined. These waves are widely used in medical practice as a means of physiotherapy for the treatment of various human disorders. Principal attention is given to the mechanisms through which millimeter waves act on the human organism.

  4. Stabilization of Protein-Protein Interactions in chemical biology and drug discovery.

    Science.gov (United States)

    Bier, David; Thiel, Philipp; Briels, Jeroen; Ottmann, Christian

    2015-10-01

    More than 300,000 Protein-Protein Interactions (PPIs) can be found in human cells. This number is significantly larger than the number of single proteins, which are the classical targets for pharmacological intervention. Hence, specific and potent modulation of PPIs by small, drug-like molecules would tremendously enlarge the "druggable genome" enabling novel ways of drug discovery for essentially every human disease. This strategy is especially promising in diseases with difficult targets like intrinsically disordered proteins or transcription factors, for example neurodegeneration or metabolic diseases. Whereas the potential of PPI modulation has been recognized in terms of the development of inhibitors that disrupt or prevent a binary protein complex, the opposite (or complementary) strategy to stabilize PPIs has not yet been realized in a systematic manner. This fact is rather surprising given the number of impressive natural product examples that confer their activity by stabilizing specific PPIs. In addition, in recent years more and more examples of synthetic molecules are being published that work as PPI stabilizers, despite the fact that in the majority they initially have not been designed as such. Here, we describe examples from both the natural products as well as the synthetic molecules advocating for a stronger consideration of the PPI stabilization approach in chemical biology and drug discovery. PMID:26093250

  5. Commercially available interactive video games in burn rehabilitation: therapeutic potential.

    Science.gov (United States)

    Parry, Ingrid S; Bagley, Anita; Kawada, Jason; Sen, Soman; Greenhalgh, David G; Palmieri, Tina L

    2012-06-01

    Commercially available interactive video games (IVG) like the Nintendo Wii™ (NW) and PlayStation™II Eye Toy (PE) are increasingly used in the rehabilitation of patients with burn. Such games have gained popularity in burn rehabilitation because they encourage range of motion (ROM) while distracting from pain. However, IVGs were not originally designed for rehabilitation purposes but rather for entertainment and may lack specificity for achieving rehabilitative goals. Objectively evaluating the specific demands of IVGs in relation to common burn therapy goals will determine their true therapeutic benefit and guide their use in burn rehabilitation. Upper extremity (UE) motion of 24 normal children was measured using 3D motion analysis during play with the two types of IVGs most commonly described for use after burn: NW and PE. Data was analyzed using t-tests and One-way Analysis of Variance. Active range of motion for shoulder flexion and abduction during play with both PE and NW was within functional range, thus supporting the idea that IVGs offer activities with therapeutic potential to improve ROM. PE resulted in higher demands and longer duration of UE motion than NW, and therefore may be the preferred tool when UE ROM or muscular endurance are the goals of rehabilitation. When choosing a suitable IVG for application in rehabilitation, the user's impairment together with the therapeutic attributes of the IVG should be considered to optimize outcome. PMID:22385641

  6. Probiotics: Interaction with gut microbiome and antiobesity potential.

    Science.gov (United States)

    Arora, Tulika; Singh, Satvinder; Sharma, Raj Kumar

    2013-04-01

    Obesity is a metabolic disorder afflicting people globally. There has been a pivotal advancement in the understanding of the intestinal microbiota composition and its implication in extraintestinal (metabolic) diseases. Therefore, any agent modulating gut microbiota may produce an influential effect in preventing the pathogenesis of disease. Probiotics are live microbes that, when administered in adequate amounts, have been shown to confer health benefits to the host. Over the years, probiotics have been a part of the human diet in the form of different fermented foods consumed around the world. Their influence on different physiologic functions in the host is increasingly being documented. The antiobesity potential of probiotics is also gaining wide attention because of increasing evidence of the role of gut microbiota in energy homeostasis and fat accumulation. Probiotics have also been shown to interact with the resident bacterial members already present in the gut by altering their properties, which may also affect the metabolic pathways involved in the regulation of fat metabolism. The underlying pathways governing the antiobesity effects of probiotics remain unclear. However, it is hoped that the evidence presented and discussed in this review will encourage and thus drive more extensive research in this field.

  7. Biana: a software framework for compiling biological interactions and analyzing networks

    Directory of Open Access Journals (Sweden)

    Planas-Iglesias Joan

    2010-01-01

    Full Text Available Abstract Background The analysis and usage of biological data is hindered by the spread of information across multiple repositories and the difficulties posed by different nomenclature systems and storage formats. In particular, there is an important need for data unification in the study and use of protein-protein interactions. Without good integration strategies, it is difficult to analyze the whole set of available data and its properties. Results We introduce BIANA (Biologic Interactions and Network Analysis, a tool for biological information integration and network management. BIANA is a Python framework designed to achieve two major goals: i the integration of multiple sources of biological information, including biological entities and their relationships, and ii the management of biological information as a network where entities are nodes and relationships are edges. Moreover, BIANA uses properties of proteins and genes to infer latent biomolecular relationships by transferring edges to entities sharing similar properties. BIANA is also provided as a plugin for Cytoscape, which allows users to visualize and interactively manage the data. A web interface to BIANA providing basic functionalities is also available. The software can be downloaded under GNU GPL license from http://sbi.imim.es/web/BIANA.php. Conclusions BIANA's approach to data unification solves many of the nomenclature issues common to systems dealing with biological data. BIANA can easily be extended to handle new specific data repositories and new specific data types. The unification protocol allows BIANA to be a flexible tool suitable for different user requirements: non-expert users can use a suggested unification protocol while expert users can define their own specific unification rules.

  8. Induced gravity with Higgs potential. Elementary interactions and quantum processes

    Energy Technology Data Exchange (ETDEWEB)

    Bezares Roder, Nils Manuel

    2010-07-01

    This work is intended to first serve as introduction in fundamental subjects of physics in order to be then able to review the mechanism of symmetry breakdown and its essential character in physics. It introduces the concept of scalar-tensor theories of gravity based on Bergmann-Wagoner models with a Higgs potential. The main physical context aimed is the problem of Dark Matter and Dark Energy. On the one hand, there is gravitation. Within this context, we have Dark Matter as an especially relevant concept. This work entails the following main contributions: - General features of Einstein's theory are introduced together with generalities of the different elementary interactions of physics from which the concepts of dark sectors and Higgs Mechanism are derived. - The concept of symmetry breaking and especially the Higgs Mechanism of mass generation are discussed in their relevance for the most different subjects of physics, especially in relation to the Standard Model of elementary particle physics with elementary Higgs fields. - Scalar-Tensor Theories are introduced in order to build in them the process of Higgs Mechanism. This is then fulfilled with a theory of induced gravity with a Higgs potential which seems renormalizable according to deWitt's power counting criterion, and with mass-generating Higgs fields which only couple gravitationally as well as with Higgs fields which act analogously to cosmon fields. - Further, the energy density of the gravitational field is derived for the specific model of induced gravity from an analogy to electrodynamics. It is shown that a nonvanishing value of pressure related to the scalar field is necessary in order to reproduce standard linear solar-relativistic dynamics. Within astrophysical considerations for flat rotation curves of galaxies, a possible dark-matter behavior is concluded within spherical symmetry. The scalar field and the dark-matter profile of total energy density are derived. An analogous

  9. Induced gravity with Higgs potential. Elementary interactions and quantum processes

    International Nuclear Information System (INIS)

    This work is intended to first serve as introduction in fundamental subjects of physics in order to be then able to review the mechanism of symmetry breakdown and its essential character in physics. It introduces the concept of scalar-tensor theories of gravity based on Bergmann-Wagoner models with a Higgs potential. The main physical context aimed is the problem of Dark Matter and Dark Energy. On the one hand, there is gravitation. Within this context, we have Dark Matter as an especially relevant concept. This work entails the following main contributions: - General features of Einstein's theory are introduced together with generalities of the different elementary interactions of physics from which the concepts of dark sectors and Higgs Mechanism are derived. - The concept of symmetry breaking and especially the Higgs Mechanism of mass generation are discussed in their relevance for the most different subjects of physics, especially in relation to the Standard Model of elementary particle physics with elementary Higgs fields. - Scalar-Tensor Theories are introduced in order to build in them the process of Higgs Mechanism. This is then fulfilled with a theory of induced gravity with a Higgs potential which seems renormalizable according to deWitt's power counting criterion, and with mass-generating Higgs fields which only couple gravitationally as well as with Higgs fields which act analogously to cosmon fields. - Further, the energy density of the gravitational field is derived for the specific model of induced gravity from an analogy to electrodynamics. It is shown that a nonvanishing value of pressure related to the scalar field is necessary in order to reproduce standard linear solar-relativistic dynamics. Within astrophysical considerations for flat rotation curves of galaxies, a possible dark-matter behavior is concluded within spherical symmetry. The scalar field and the dark-matter profile of total energy density are derived. An analogous relation between

  10. Removal of disinfection by-product formation potentials by biologically assisted GAC treatment

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The object of this paper is to evaluate the removal of disinfection by-products formation potential by artificially intensified biological activated carbon(BAC) process which is developed on the basis of traditional ozone granular activated carbon (GAC). The results show that 23.1% of trihalomethane formation potential (THMFP) and 68% of haloacetic acid formation potential (HAAFP) can be removed by BAC,respectively. Under the same conditions, the removal rates of the same substances were 12.2% and 13-25 % respectively only by GAC process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. BAC process has some advantages such as long backwashing cycle time, low backwashing intensity and prolonged activated carbon lifetime, etc.

  11. The potential of plants as a system for the development and production of human biologics

    OpenAIRE

    Qiang Chen; Davis, Keith R.

    2016-01-01

    The growing promise of plant-made biologics is highlighted by the success story of ZMapp™ as a potentially life-saving drug during the Ebola outbreak of 2014-2016. Current plant expression platforms offer features beyond the traditional advantages of low cost, high scalability, increased safety, and eukaryotic protein modification. Novel transient expression vectors have been developed that allow the production of vaccines and therapeutics at unprecedented speed to control potential pandemics...

  12. Microorganisms in potential host rocks for geological disposal of nuclear waste and their interactions with radionuclides

    International Nuclear Information System (INIS)

    The long-term safety of nuclear waste in a deep geological repository is an important issue in our society. Microorganisms indigenous to potential host rocks are able to influence the oxidation state, speciation and therefore the mobility of radionuclides as well as gas generation or canister corrosion. Therefore, for the safety assessment of such a repository it is necessary to know which microorganisms are present in the potential host rocks (e.g. clay, salt) and if these microorganisms can influence the performance of a repository. Microbial diversity in potential host rocks for geological disposal of nuclear waste was analyzed by culture-independent molecular biological methods (e.g. 16S rRNA gene retrieval) as well as enrichment and isolation of indigenous microbes. Among other isolates, a Paenibacillus strain, as a representative of Firmicutes, was recovered in R2A media under anaerobic conditions from Opalinus clay from the Mont Terri in Switzerland. Accumulation experiments and potentiometric titrations showed a strong interaction of Paenibacillus sp. cells with U(VI) within a broad pH range (3-7). Additionally, the interactions of the halophilic archaeal strain Halobacterium noricense DSM 15987, a salt rock representative reference strain, with U(VI) at high ionic strength was investigated. After 48 h the cells were still alive at uranium concentrations up to 60 μM, which demonstrates that Halobacterium noricense can tolerate uranium concentrations up to this level. The formed uranium sorption species were examined with time-resolved laser-induced fluorescence spectroscopy (TRLFS). The results about the microbial communities present in potential host rocks for nuclear waste repositories and their interactions with radionuclides contribute to the safety assessment of a prospective nuclear waste repository.

  13. Microorganisms in potential host rocks for geological disposal of nuclear waste and their interactions with radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Cherkouk, A.; Liebe, M.; Luetke, L.; Moll, H.; Stumpf, T. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Inst. of Resource Ecology

    2015-07-01

    The long-term safety of nuclear waste in a deep geological repository is an important issue in our society. Microorganisms indigenous to potential host rocks are able to influence the oxidation state, speciation and therefore the mobility of radionuclides as well as gas generation or canister corrosion. Therefore, for the safety assessment of such a repository it is necessary to know which microorganisms are present in the potential host rocks (e.g. clay, salt) and if these microorganisms can influence the performance of a repository. Microbial diversity in potential host rocks for geological disposal of nuclear waste was analyzed by culture-independent molecular biological methods (e.g. 16S rRNA gene retrieval) as well as enrichment and isolation of indigenous microbes. Among other isolates, a Paenibacillus strain, as a representative of Firmicutes, was recovered in R2A media under anaerobic conditions from Opalinus clay from the Mont Terri in Switzerland. Accumulation experiments and potentiometric titrations showed a strong interaction of Paenibacillus sp. cells with U(VI) within a broad pH range (3-7). Additionally, the interactions of the halophilic archaeal strain Halobacterium noricense DSM 15987, a salt rock representative reference strain, with U(VI) at high ionic strength was investigated. After 48 h the cells were still alive at uranium concentrations up to 60 μM, which demonstrates that Halobacterium noricense can tolerate uranium concentrations up to this level. The formed uranium sorption species were examined with time-resolved laser-induced fluorescence spectroscopy (TRLFS). The results about the microbial communities present in potential host rocks for nuclear waste repositories and their interactions with radionuclides contribute to the safety assessment of a prospective nuclear waste repository.

  14. Biophysics of DNA-Protein Interactions From Single Molecules to Biological Systems

    CERN Document Server

    Williams, Mark C

    2011-01-01

    This book presents a concise overview of current research on the biophysics of DNA-protein interactions. A wide range of new and classical methods are presented by authors investigating physical mechanisms by which proteins interact with DNA. For example, several chapters address the mechanisms by which proteins search for and recognize specific binding sites on DNA, a process critical for cellular function. Single molecule methods such as force spectroscopy as well as fluorescence imaging and tracking are described in these chapters as well as other parts of the book that address the dynamics of protein-DNA interactions. Other important topics include the mechanisms by which proteins engage DNA sequences and/or alter DNA structure. These simple but important model interactions are then placed in the broader biological context with discussion of larger protein-DNA complexes . Topics include replication forks, recombination complexes, DNA repair interactions, and ultimately, methods to understand the chromatin...

  15. A review on protein-protein interaction network of APE1/Ref-1 and its associated biological functions.

    Science.gov (United States)

    Thakur, S; Dhiman, M; Tell, G; Mantha, A K

    2015-04-01

    Apurinic/apyrimidinic endonuclease 1 (APE1) is a classic example of functionally variable protein. Besides its well-known role in (i) DNA repair of oxidative base damage, APE1 also plays a critical role in (ii) redox regulation of transcription factors controlling gene expression for cell survival pathways, for which it is also known as redox effector factor 1 (Ref-1), and recent evidences advocates for (iii) coordinated control of other non-canonical protein-protein interaction(s) responsible for significant biological functions in mammalian cells. The diverse functions of APE1 can be ascribed to its ability to interact with different protein partners, owing to the attainment of unfolded domains during evolution. Association of dysregulation of APE1 with various human pathologies, such as cancer, cardiovascular diseases and neurodegeneration, is attributable to its multifunctional nature, and this makes APE1 a potential therapeutic target. This review covers the important aspects of APE1 in terms of its significant protein-protein interaction(s), and this knowledge is required to understand the onset and development of human pathologies and to design or improve the strategies to target such interactions for treatment and management of various human diseases.

  16. Anticoagulant Medicine: Potential for Drug-Food Interactions

    Science.gov (United States)

    ... AerobiKa® Cardiology Medications Anticoagulant Medicine Anticoagulants and Drug-Food Interactions COPD Medications Bronchodilators Anti-Inflammatories Antibiotics Managing Your Medications Devices ...

  17. Mass spectrometry in structural biology and biophysics architecture, dynamics, and interaction of biomolecules

    CERN Document Server

    Kaltashov, Igor A; Desiderio, Dominic M; Nibbering, Nico M

    2012-01-01

    The definitive guide to mass spectrometry techniques in biology and biophysics The use of mass spectrometry (MS) to study the architecture and dynamics of proteins is increasingly common within the biophysical community, and Mass Spectrometry in Structural Biology and Biophysics: Architecture, Dynamics, and Interaction of Biomolecules, Second Edition provides readers with detailed, systematic coverage of the current state of the art. Offering an unrivalled overview of modern MS-based armamentarium that can be used to solve the most challenging problems in biophysics, structural biol

  18. Peptidyl anthraquinones as potential antineoplastic drugs: synthesis, DNA binding, redox cycling, and biological activity.

    Science.gov (United States)

    Gatto, B; Zagotto, G; Sissi, C; Cera, C; Uriarte, E; Palù, G; Capranico, G; Palumbo, M

    1996-08-01

    A series of new compounds containing a 9,10-anthracenedione moiety and one or two peptide chains at position 1 and/or 4 have been synthesized. The amino acid residues introduced are glycine (Gly), lysine (Lys), and tryptophan (Trp), the latter two in both the L- and D-configurations. The peptidyl anthraquinones maintain the ability of intercalating efficiently into DNA, even though the orientation within the base-pair pocket may change somewhat with reference to the parent drugs mitoxantrone (MX) and ametantrone (AM). The interaction constants of the mono-, di-, and triglycyl derivatives are well comparable to those found for AM but 5-10 times lower than the value reported for MX. On the other hand, the glycyl-lysyl compounds bind DNA to the same extent as (L-isomer) or even better than (D-isomer) MX. As for the parent drugs without peptidyl chains, the new compounds prefer alternating CG binding sites, although to different extents. The bis-Gly-Lys derivatives are the least sensitive to base composition, which may be due to extensive aspecific charged interactions with the polynucleotide backbone. As far as redox properties are concerned, all peptidyl anthraquinones show a reduction potential very close to that of AM and 60-80 mV less negative than that of MX; hence, they can produce free-radical-damaging species to an extent similar to the parent drugs. The biological activity has been tested in human tumor and murine leukemia cell lines. Most of the test anthraquinones exhibit cytotoxic properties close to those of AM and considerably lower than those of MX. Stimulation of topoisomerase-mediated DNA cleavage is moderately present in representatives of the glycylanthraquinone family, whereas inhibition of the background cleavage occurs when Lys is present in the peptide chain. For most of the test anthraquinones, the toxicity data are in line with the DNA affinity scale and the topoisomerase II stimulation activity. However, in the lysyl derivatives, for which

  19. Molecular Insights into the Potential Toxicological Interaction of 2-Mercaptothiazoline with the Antioxidant Enzyme—Catalase

    Science.gov (United States)

    Huang, Zhenxing; Huang, Ming; Mi, Chenyu; Wang, Tao; Chen, Dong; Teng, Yue

    2016-01-01

    2-mercaptothiazoline (2-MT) is widely used in many industrial fields, but its residue is potentially harmful to the environment. In this study, to evaluate the biological toxicity of 2-MT at protein level, the interaction between 2-MT and the pivotal antioxidant enzyme—catalase (CAT) was investigated using multiple spectroscopic techniques and molecular modeling. The results indicated that the CAT fluorescence quenching caused by 2-MT should be dominated by a static quenching mechanism through formation of a 2-MT/CAT complex. Furthermore, the identifications of the binding constant, binding forces, and the number of binding sites demonstrated that 2-MT could spontaneously interact with CAT at one binding site mainly via Van der Waals’ forces and hydrogen bonding. Based on the molecular docking simulation and conformation dynamic characterization, it was found that 2-MT could bind into the junctional region of CAT subdomains and that the binding site was close to enzyme active sites, which induced secondary structural and micro-environmental changes in CAT. The experiments on 2-MT toxicity verified that 2-MT significantly inhibited CAT activity via its molecular interaction, where 2-MT concentration and exposure time both affected the inhibitory action. Therefore, the present investigation provides useful information for understanding the toxicological mechanism of 2-MT at the molecular level. PMID:27537873

  20. Molecular mechanisms of nematode-nematophagous microbe interactions: basis for biological control of plant-parasitic nematodes.

    Science.gov (United States)

    Li, Juan; Zou, Chenggang; Xu, Jianping; Ji, Xinglai; Niu, Xuemei; Yang, Jinkui; Huang, Xiaowei; Zhang, Ke-Qin

    2015-01-01

    Plant-parasitic nematodes cause significant damage to a broad range of vegetables and agricultural crops throughout the world. As the natural enemies of nematodes, nematophagous microorganisms offer a promising approach to control the nematode pests. Some of these microorganisms produce traps to capture and kill the worms from the outside. Others act as internal parasites to produce toxins and virulence factors to kill the nematodes from within. Understanding the molecular basis of microbe-nematode interactions provides crucial insights for developing effective biological control agents against plant-parasitic nematodes. Here, we review recent advances in our understanding of the interactions between nematodes and nematophagous microorganisms, with a focus on the molecular mechanisms by which nematophagous microorganisms infect nematodes and on the nematode defense against pathogenic attacks. We conclude by discussing several key areas for future research and development, including potential approaches to apply our recent understandings to develop effective biocontrol strategies. PMID:25938277

  1. Molecular mechanisms of nematode-nematophagous microbe interactions: basis for biological control of plant-parasitic nematodes.

    Science.gov (United States)

    Li, Juan; Zou, Chenggang; Xu, Jianping; Ji, Xinglai; Niu, Xuemei; Yang, Jinkui; Huang, Xiaowei; Zhang, Ke-Qin

    2015-01-01

    Plant-parasitic nematodes cause significant damage to a broad range of vegetables and agricultural crops throughout the world. As the natural enemies of nematodes, nematophagous microorganisms offer a promising approach to control the nematode pests. Some of these microorganisms produce traps to capture and kill the worms from the outside. Others act as internal parasites to produce toxins and virulence factors to kill the nematodes from within. Understanding the molecular basis of microbe-nematode interactions provides crucial insights for developing effective biological control agents against plant-parasitic nematodes. Here, we review recent advances in our understanding of the interactions between nematodes and nematophagous microorganisms, with a focus on the molecular mechanisms by which nematophagous microorganisms infect nematodes and on the nematode defense against pathogenic attacks. We conclude by discussing several key areas for future research and development, including potential approaches to apply our recent understandings to develop effective biocontrol strategies.

  2. Bioactive protein-based nanofibers interact with intestinal biological components resulting in transepithelial permeation of a therapeutic protein

    DEFF Research Database (Denmark)

    Boutrup Stephansen, Karen; García-Díaz, María; Jessen, Flemming;

    2015-01-01

    Proteins originating from natural sources may constitute a novel type of material for use in drug delivery. However, thorough understanding of the behavior and effects of such a material when processed into a matrix together with a drug is crucial prior to further development into a drug product....... In the present study the potential of using bioactive electrospun fish sarcoplasmic proteins (FSP) as a carrier matrix for small therapeutic proteins was demonstrated in relation to the interactions with biological components of the intestinal tract. The inherent structural and chemical properties of FSP...... as a biomaterial facilitated interactions with cells and enzymes found in the gastrointestinal tract and displayed excellent biocompatibility. More specifically, insulin was efficiently encapsulated into FSP fibers maintaining its conformation, and subsequent controlled release was obtained in simulated intestinal...

  3. The potential of plants as a system for the development and production of human biologics.

    Science.gov (United States)

    Chen, Qiang; Davis, Keith R

    2016-01-01

    The growing promise of plant-made biologics is highlighted by the success story of ZMapp™ as a potentially life-saving drug during the Ebola outbreak of 2014-2016. Current plant expression platforms offer features beyond the traditional advantages of low cost, high scalability, increased safety, and eukaryotic protein modification. Novel transient expression vectors have been developed that allow the production of vaccines and therapeutics at unprecedented speed to control potential pandemics or bioterrorism attacks. Plant-host engineering provides a method for producing proteins with unique and uniform mammalian post-translational modifications, providing opportunities to develop biologics with increased efficacy relative to their mammalian cell-produced counterparts. Recent demonstrations that plant-made proteins can function as biocontrol agents of foodborne pathogens further exemplify the potential utility of plant-based protein production. However, resolving the technical and regulatory challenges of commercial-scale production, garnering acceptance from large pharmaceutical companies, and obtaining U.S. Food and Drug Administration approval for several major classes of biologics are essential steps to fulfilling the untapped potential of this technology. PMID:27274814

  4. The potential of plants as a system for the development and production of human biologics

    Science.gov (United States)

    Chen, Qiang; Davis, Keith R.

    2016-01-01

    The growing promise of plant-made biologics is highlighted by the success story of ZMapp™ as a potentially life-saving drug during the Ebola outbreak of 2014-2016. Current plant expression platforms offer features beyond the traditional advantages of low cost, high scalability, increased safety, and eukaryotic protein modification. Novel transient expression vectors have been developed that allow the production of vaccines and therapeutics at unprecedented speed to control potential pandemics or bioterrorism attacks. Plant-host engineering provides a method for producing proteins with unique and uniform mammalian post-translational modifications, providing opportunities to develop biologics with increased efficacy relative to their mammalian cell-produced counterparts. Recent demonstrations that plant-made proteins can function as biocontrol agents of foodborne pathogens further exemplify the potential utility of plant-based protein production. However, resolving the technical and regulatory challenges of commercial-scale production, garnering acceptance from large pharmaceutical companies, and obtaining U.S. Food and Drug Administration approval for several major classes of biologics are essential steps to fulfilling the untapped potential of this technology. PMID:27274814

  5. The potential of plants as a system for the development and production of human biologics.

    Science.gov (United States)

    Chen, Qiang; Davis, Keith R

    2016-01-01

    The growing promise of plant-made biologics is highlighted by the success story of ZMapp™ as a potentially life-saving drug during the Ebola outbreak of 2014-2016. Current plant expression platforms offer features beyond the traditional advantages of low cost, high scalability, increased safety, and eukaryotic protein modification. Novel transient expression vectors have been developed that allow the production of vaccines and therapeutics at unprecedented speed to control potential pandemics or bioterrorism attacks. Plant-host engineering provides a method for producing proteins with unique and uniform mammalian post-translational modifications, providing opportunities to develop biologics with increased efficacy relative to their mammalian cell-produced counterparts. Recent demonstrations that plant-made proteins can function as biocontrol agents of foodborne pathogens further exemplify the potential utility of plant-based protein production. However, resolving the technical and regulatory challenges of commercial-scale production, garnering acceptance from large pharmaceutical companies, and obtaining U.S. Food and Drug Administration approval for several major classes of biologics are essential steps to fulfilling the untapped potential of this technology.

  6. Information theory in systems biology. Part II: protein-protein interaction and signaling networks.

    Science.gov (United States)

    Mousavian, Zaynab; Díaz, José; Masoudi-Nejad, Ali

    2016-03-01

    By the development of information theory in 1948 by Claude Shannon to address the problems in the field of data storage and data communication over (noisy) communication channel, it has been successfully applied in many other research areas such as bioinformatics and systems biology. In this manuscript, we attempt to review some of the existing literatures in systems biology, which are using the information theory measures in their calculations. As we have reviewed most of the existing information-theoretic methods in gene regulatory and metabolic networks in the first part of the review, so in the second part of our study, the application of information theory in other types of biological networks including protein-protein interaction and signaling networks will be surveyed.

  7. Experimental Evidence of Biological Interactions among Different Isolates of Trypanosoma cruzi from the Chaco Region

    Science.gov (United States)

    Ragone, Paula G.; Pérez Brandán, Cecilia; Monje Rumi, Mercedes; Tomasini, Nicolás; Lauthier, Juan J.; Cimino, Rubén O.; Uncos, Alejandro; Ramos, Federico; Alberti D´Amato, Anahí M.; Basombrío, Miguel A.; Diosque, Patricio

    2015-01-01

    Many infectious diseases arise from co-infections or re-infections with more than one genotype of the same pathogen. These mixed infections could alter host fitness, the severity of symptoms, success in pathogen transmission and the epidemiology of the disease. Trypanosoma cruzi, the etiological agent of Chagas disease, exhibits a high biological variability often correlated with its genetic diversity. Here, we developed an experimental approach in order to evaluate biological interaction between three T. cruzi isolates belonging to different Discrete Typing Units (DTUs TcIII, TcV and TcVI). These isolates were obtained from a restricted geographical area in the Chaco Region. Different mixed infections involving combinations of two isolates (TcIII + TcV, TcIII + TcVI and TcV + TcVI) were studied in a mouse model. The parameters evaluated were number of parasites circulating in peripheral blood, histopathology and genetic characterization of each DTU in different tissues by DNA hybridization probes. We found a predominance of TcVI isolate in blood and tissues respect to TcIII and TcV; and a decrease of the inflammatory response in heart when the damage of mice infected with TcVI and TcIII + TcVI mixture were compared. In addition, simultaneous presence of two isolates in the same tissue was not detected. Our results show that biological interactions between isolates with different biological behaviors lead to changes in their biological properties. The occurrence of interactions among different genotypes of T. cruzi observed in our mouse model suggests that these phenomena could also occur in natural cycles in the Chaco Region. PMID:25789617

  8. Experimental evidence of biological interactions among different isolates of Trypanosoma cruzi from the Chaco Region.

    Directory of Open Access Journals (Sweden)

    Paula G Ragone

    Full Text Available Many infectious diseases arise from co-infections or re-infections with more than one genotype of the same pathogen. These mixed infections could alter host fitness, the severity of symptoms, success in pathogen transmission and the epidemiology of the disease. Trypanosoma cruzi, the etiological agent of Chagas disease, exhibits a high biological variability often correlated with its genetic diversity. Here, we developed an experimental approach in order to evaluate biological interaction between three T. cruzi isolates belonging to different Discrete Typing Units (DTUs TcIII, TcV and TcVI. These isolates were obtained from a restricted geographical area in the Chaco Region. Different mixed infections involving combinations of two isolates (TcIII + TcV, TcIII + TcVI and TcV + TcVI were studied in a mouse model. The parameters evaluated were number of parasites circulating in peripheral blood, histopathology and genetic characterization of each DTU in different tissues by DNA hybridization probes. We found a predominance of TcVI isolate in blood and tissues respect to TcIII and TcV; and a decrease of the inflammatory response in heart when the damage of mice infected with TcVI and TcIII + TcVI mixture were compared. In addition, simultaneous presence of two isolates in the same tissue was not detected. Our results show that biological interactions between isolates with different biological behaviors lead to changes in their biological properties. The occurrence of interactions among different genotypes of T. cruzi observed in our mouse model suggests that these phenomena could also occur in natural cycles in the Chaco Region.

  9. Biomolecular Interactions and Biological Responses of Emerging Two-Dimensional Materials and Aromatic Amino Acid Complexes.

    Science.gov (United States)

    Mallineni, Sai Sunil Kumar; Shannahan, Jonathan; Raghavendra, Achyut J; Rao, Apparao M; Brown, Jared M; Podila, Ramakrishna

    2016-07-01

    The present work experimentally investigates the interaction of aromatic amino acids viz., tyrosine, tryptophan, and phenylalnine with novel two-dimensional (2D) materials including graphene, graphene oxide (GO), and boron nitride (BN). Photoluminescence, micro-Raman spectroscopy, and cyclic voltammetry were employed to investigate the nature of interactions and possible charge transfer between 2D materials and amino acids. Graphene and GO were found to interact strongly with aromatic amino acids through π-π stacking, charge transfer, and H-bonding. Particularly, it was observed that both physi and chemisorption are prominent in the interactions of GO/graphene with phenylalanine and tryptophan while tyrosine exhibited strong chemisorption on graphene and GO. In contrast, BN exhibited little or no interactions, which could be attributed to localized π-electron clouds around N atoms in BN lattice. Lastly, the adsorption of amino acids on 2D materials was observed to considerably change their biological response in terms of reactive oxygen species generation. More importantly, these changes in the biological response followed the same trends observed in the physi and chemisorption measurements. PMID:27281436

  10. Sialoglycoconjugates in Trypanosoma cruzi-host cell interaction: possible biological model - a review

    Directory of Open Access Journals (Sweden)

    Alane Beatriz Vermelho

    1994-03-01

    Full Text Available A number of glycoconjugates, including glycolipids and glycoproteins, participate in the process of host-cell invasion by Trypanosoma cruzi and one of the most important carbohydrates involved on this interaction is sialic acid. It is known that parasite trans-sialidase participates with sialic acid in a coordinated fashion in the initial stages of invasion. Given the importance of these sialogycoconjugates, this review sets out various possible biological models for the interaction between the parasite and mammalian cells that possess a sialylated receptor/ligand system.

  11. Kinetic limits for pair-interaction driven master equations and biological swarm models

    OpenAIRE

    Carlen, Eric; Degond, Pierre; Wennberg, Bernt

    2011-01-01

    We consider a class of stochastic processes modeling binary interactions in an N-particle system. Examples of such systems can be found in the modeling of biological swarms. They lead to the definition of a class of master equations that we call pair interaction driven master equations. We prove a propagation of chaos result for this class of master equations which generalizes Mark Kac's well know result for the Kac model in kinetic theory. We use this result to study kinetic limits for two b...

  12. The Potential for the Integration of Nuclear Techniques in Arthropod Biological Control

    International Nuclear Information System (INIS)

    Biological control is today being practised more widely than ever before and its popularity looks set to increase further in the future. While the discipline has historically been dominated by 'classical' biological control (the one-off introduction of natural enemies to control pests in their adventive range) augmentative biological control (the repeated introduction of biocontrol agents to a particular crop or forest) has increased substantially over the past 20 years and is likely to increase in importance further in the future. This view is supported by an assessment of some of the key issues facing the discipline of biological control today. There is no clear role for nuclear techniques in the future of classical biological control. However the use of irradiation as a means of creating increased rates of mutation in natural enemy populations being selected for enhanced beneficial traits (such as insecticide resistance), might be useful and could be investigated further. There is scope for the use of irradiation in killing or sterilising insect diets and hosts, a technique which has been used for over 25 years without gaining wide acceptance. Augmentative biological control as an adjunct to SIT may have a role in future pest control campaigns, although it is likely to prove difficult to provide a clear economic justification given the technical difficulties of measuring separately the effects of the two techniques. It is suggested that the technical advances in project development and implementation (e.g. insect rearing techniques and field application) which have been made by SIT practitioners have a potentially useful role in assisting the development of improved production and delivery of biological control agents for augmentative release (author)

  13. Biclustering with Flexible Plaid Models to Unravel Interactions between Biological Processes.

    Science.gov (United States)

    Henriques, Rui; Madeira, Sara C

    2015-01-01

    Genes can participate in multiple biological processes at a time and thus their expression can be seen as a composition of the contributions from the active processes. Biclustering under a plaid assumption allows the modeling of interactions between transcriptional modules or biclusters (subsets of genes with coherence across subsets of conditions) by assuming an additive composition of contributions in their overlapping areas. Despite the biological interest of plaid models, few biclustering algorithms consider plaid effects and, when they do, they place restrictions on the allowed types and structures of biclusters, and suffer from robustness problems by seizing exact additive matchings. We propose BiP (Biclustering using Plaid models), a biclustering algorithm with relaxations to allow expression levels to change in overlapping areas according to biologically meaningful assumptions (weighted and noise-tolerant composition of contributions). BiP can be used over existing biclustering solutions (seizing their benefits) as it is able to recover excluded areas due to unaccounted plaid effects and detect noisy areas non-explained by a plaid assumption, thus producing an explanatory model of overlapping transcriptional activity. Experiments on synthetic data support BiP's efficiency and effectiveness. The learned models from expression data unravel meaningful and non-trivial functional interactions between biological processes associated with putative regulatory modules. PMID:26357312

  14. Using consumption rate to assess potential predators for biological control of white perch

    Science.gov (United States)

    Gosch, N.J.C.; Pope, K.L.

    2011-01-01

    Control of undesirable fishes is important in aquatic systems, and using predation as a tool for biological control is an attractive option to fishery biologists. However, determining the appropriate predators for biological control is critical for success. The objective of this study was to evaluate the utility of consumption rate as an index to determine the most effective predators for biological control of an invasive fish. Consumption rate values were calculated for nine potential predators that prey on white perch Morone americana in Branched Oak and Pawnee reservoirs, Nebraska. The consumption rate index provided a unique and insightful means of determining the potential effectiveness of each predator species in controlling white perch. Cumulative frequency distributions facilitated interpretation by providing a graphical presentation of consumption rates by all individuals within each predator species. Largemouth bass Micropterus salmoides, walleye Sander vitreus and sauger S. canadensis were the most efficient white perch predators in both reservoirs; however, previous attempts to increase biomass of these predators have failed suggesting that successful biological control is unlikely using existing predator species in these Nebraska reservoirs. ?? 2011 ONEMA.

  15. CD26/dipeptidylpeptidase IV-chemokine interactions: double-edged regulation of inflammation and tumor biology.

    Science.gov (United States)

    Mortier, Anneleen; Gouwy, Mieke; Van Damme, Jo; Proost, Paul; Struyf, Sofie

    2016-06-01

    Post-translational modification of chemokines is an essential regulatory mechanism to enhance or dampen the inflammatory response. CD26/dipeptidylpeptidase IV, ubiquitously expressed in tissues and blood, removes NH2-terminal dipeptides from proteins with a penultimate Pro or Ala. A large number of human chemokines, including CXCL2, CXCL6, CXCL9, CXCL10, CXCL11, CXCL12, CCL3L1, CCL4, CCL5, CCL11, CCL14, and CCL22, are cleaved by CD26; however, the efficiency is clearly influenced by the amino acids surrounding the cleavage site and although not yet proven, potentially affected by the chemokine concentration and interactions with third molecules. NH2-terminal cleavage of chemokines by CD26 has prominent effects on their receptor binding, signaling, and hence, in vitro and in vivo biologic activities. However, rather than having a similar result, the outcome of NH2-terminal truncation is highly diverse. Either no difference in activity or drastic alterations in receptor recognition/specificity and hence, chemotactic activity are observed. Analogously, chemokine-dependent inhibition of HIV infection is enhanced (for CCL3L1 and CCL5) or decreased (for CXCL12) by CD26 cleavage. The occurrence of CD26-processed chemokine isoforms in plasma underscores the importance of the in vitro-observed CD26 cleavages. Through modulation of chemokine activity, CD26 regulates leukocyte/tumor cell migration and progenitor cell release from the bone marrow, as shown by use of mice treated with CD26 inhibitors or CD26 knockout mice. As chemokine processing by CD26 has a significant impact on physiologic and pathologic processes, application of CD26 inhibitors to affect chemokine function is currently explored, e.g., as add-on therapy in viral infection and cancer. PMID:26744452

  16. Interaction of biological systems with static and ELF electric and magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, L.E.; Kelman, B.J.; Weigel, R.J. (eds.)

    1987-01-01

    Although background levels of atmospheric electric and geomagnetic field levels are extremely low, over the past several decades, human beings and other life forms on this planet have been subjected to a dramatically changing electromagnetic milieu. An exponential increase in exposure to electromagnetic fields has occurred, largely because of such technological advances as the growth of electrical power generation and transmission systems, the increased use of wireless communications, and the use of radar. In addition, electromagnetic field generating devices have proliferated in industrial plants, office buildings, homes, public transportation systems, and elsewhere. Although significant increases have occurred in electromagnetic field strenghths spanning all frequency ranges, this symposium addresses only the impact of these fields at static and extremely low frequencies (ELF), primarily 50 and 60 Hz. This volume contains the proceedings of the symposium entitled /open quotes/Interaction of biological systems with static and ELF electric and magnetic fields/close quotes/. The purpose of the symposium was to provide a forum for discussions of all aspects of research on the interaction of static and ELF electromagnetic fields with biological systems. These systems include simple biophysical models, cell and organ preparations, whole animals, and man. Dosimetry, exposure system design, and artifacts in ELF bioeffects research were also addressed, along with current investigations that examine fundamental mechanisms of interactions between the fields and biological processes. Papers are indexed separately.

  17. Design, Synthesis and Biological Evaluation of Benzohydrazide Derivatives Containing Dihydropyrazoles as Potential EGFR Kinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Hai-Chao Wang

    2016-08-01

    Full Text Available A series of novel benzohydrazide derivatives containing dihydropyrazoles have been synthesized as potential epidermal growth factor receptor (EGFR kinase inhibitors and their biological activities as potential antiproliferative agents have been evaluated. Among these compounds, compound H20 exhibited the most potent antiproliferative activity against four cancer cell line variants (A549, MCF-7, HeLa, HepG2 with IC50 values of 0.46, 0.29, 0.15 and 0.21 μM respectively, which showed the most potent EGFR inhibition activities (IC50 = 0.08 μM for EGFR. Molecular modeling simulation studies were performed in order to predict the biological activity and activity relationship (SAR of these benzohydrazide derivatives. These results suggested that compound H20 may be a promising anticancer agent.

  18. The Potential for Biologically Catalyzed Anaerobic Methane Oxidation on Ancient Mars

    OpenAIRE

    Marlow, Jeffrey J.; LaRowe, Douglas E.; Ehlmann, Bethany L.; Amend, Jan P.; Orphan, Victoria J

    2014-01-01

    This study examines the potential for the biologically mediated anaerobic oxidation of methane (AOM) coupled to sulfate reduction on ancient Mars. Seven distinct fluids representative of putative martian groundwater were used to calculate Gibbs energy values in the presence of dissolved methane under a range of atmospheric CO_2 partial pressures. In all scenarios, AOM is exergonic, ranging from −31 to −135 kJ/mol CH_4. A reaction transport model was constructed to examine how environmentally ...

  19. [A novel biological pathway expansion method based on the knowledge of protein-protein interactions].

    Science.gov (United States)

    Zhao, Xiaolei; Zuo, Xiaoyu; Qin, Jiheng; Liang, Yan; Zhang, Naizun; Luan, Yizhao; Rao, Shaoqi

    2014-04-01

    Biological pathways have been widely used in gene function studies; however, the current knowledge for biological pathways is per se incomplete and has to be further expanded. Bioinformatics prediction provides us a cheap but effective way for pathway expansion. Here, we proposed a novel method for biological pathway prediction, by intergrating prior knowledge of protein?protein interactions and Gene Ontology (GO) database. First, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways to which the interacting neighbors of a targe gene (at the level of protein?protein interaction) belong were chosen as the candidate pathways. Then, the pathways to which the target gene belong were determined by testing whether the genes in the candidate pathways were enriched in the GO terms to which the target gene were annotated. The protein?protein interaction data obtained from the Human Protein Reference Database (HPRD) and Biological General Repository for Interaction Datasets (BioGRID) were respectively used to predict the pathway attribution(s) of the target gene. The results demanstrated that both the average accuracy (the ratio of the correctly predicted pathways to the totally pathways to which all the target genes were annotated) and the relative accuracy (of the genes with at least one annotated pathway being successful predicted, the percentage of the genes with all the annotated pathways being correctly predicted) for pathway predictions were increased with the number of the interacting neighbours. When the number of interacting neighbours reached 22, the average accuracy was 96.2% (HPRD) and 96.3% (BioGRID), respectively, and the relative accuracy was 93.3% (HPRD) and 84.1% (BioGRID), respectively. Further validation analysis of 89 genes whose pathway knowledge was updated in a new database release indicated that 50 genes were correctly predicted for at least one updated pathway, and 43 genes were accurately predicted for all the updated pathways, giving an

  20. Mechanisms of radiation interaction with DNA: Potential implications for radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    The Office of Health and Environmental Research (OHER) of the US Department of Energy conducts a broad multidisciplinary research program which includes basic biophysics, biophysical chemistry, molecular and cellular biology as well as experimental animal studies and opportunistic human studies. This research is directed at understanding how low levels of radiation of various qualities produce the spectrum of biological effects that are seen for such exposures. This workshop was entitled ''Mechanisms of Radiation Interaction with DNA: Potential Implications for Radiation Protection.'' It ws jointly sponsored by the Department of Energy and the Commission of European Communities. The aim of the workshop was to review the base of knowledge in the area of mechanisms of radiation action at the DNA level, and to explore ways in which this information can be applied to the development of scientifically sound concepts and procedures for use in the field of radiation protection. The overview of research provided by this multidisciplinary group will be helpful to the Office in program planning. This report includes a summary of the presentations, extended abstracts, the meeting agenda, research recommendations, and a list of participants. Individual papers are processed separately for the data base.

  1. Mechanisms of radiation interaction with DNA: Potential implications for radiation protection

    International Nuclear Information System (INIS)

    The Office of Health and Environmental Research (OHER) of the US Department of Energy conducts a broad multidisciplinary research program which includes basic biophysics, biophysical chemistry, molecular and cellular biology as well as experimental animal studies and opportunistic human studies. This research is directed at understanding how low levels of radiation of various qualities produce the spectrum of biological effects that are seen for such exposures. This workshop was entitled ''Mechanisms of Radiation Interaction with DNA: Potential Implications for Radiation Protection.'' It ws jointly sponsored by the Department of Energy and the Commission of European Communities. The aim of the workshop was to review the base of knowledge in the area of mechanisms of radiation action at the DNA level, and to explore ways in which this information can be applied to the development of scientifically sound concepts and procedures for use in the field of radiation protection. The overview of research provided by this multidisciplinary group will be helpful to the Office in program planning. This report includes a summary of the presentations, extended abstracts, the meeting agenda, research recommendations, and a list of participants. Individual papers are processed separately for the data base

  2. Quantification of ultraviolet photon emission from interaction of charged particles in materials of interest in radiation biology research

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Syed Bilal, E-mail: ahmadsb@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada); Department of Physics and Applied Mathematics, Pakistan Institute of Engineering and Applied Sciences, Islamabad (Pakistan); McNeill, Fiona E., E-mail: fmcneill@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada); Prestwich, William V., E-mail: prestwic@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada); Byun, Soo Hyun, E-mail: soohyun@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada); Seymour, Colin, E-mail: seymouc@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada); Mothersill, Carmel E., E-mail: mothers@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, ON (Canada)

    2014-01-15

    In radiation biology experiments often cells are irradiated using charged particles with the intention that only a specified number of cells are hit by the primary ion track. However, in doing so several other materials such as the cell container and the growth media etc. are also irradiated, and UV radiation emitted from these materials can potentially interact with the cells. We have hypothesized that some “bystander effects” that are thought to be chemically mediated, may be, in fact, a physical effect, where UV is interacting with non-targeted cells. Based upon our hypothesis we quantified the emission of UV from Polypropylene, Mylar, Teflon, and Cellophane which are all commonly used materials in radiation biology experiments. Additionally we measured the NIST standard materials of Oyster tissue and Citrus leaves as these powdered materials are derived from living cells. Protons accelerated up to an energy of 2.2 MeV, in a 3 MV Van de Graff accelerator, were used for irradiation. Beam current was kept to 10 nA, which corresponds to a proton fluence rate of 2.7 × 10{sup 10} protons mm{sup −2} s{sup −1}. All the materials were found to emit light at UV frequencies and intensities that were significant enough to conduct a further investigation for their biological consequences. Mylar and polypropylene are commonly used in radiation induced bystander effect studies and are considered to be non-fluorescent. However our study showed that this is not the case. Significant luminescence observed from the irradiated NIST standard reference materials for Oyster tissue and Citrus leaves verified that the luminescence emission is not restricted only to the polymeric materials that are used to contain cells. It can also occur from ion interactions within the cells as well.

  3. Biological ensemble modeling to evaluate potential futures of living marine resources

    DEFF Research Database (Denmark)

    Gårdmark, Anna; Lindegren, Martin; Neuenfeldt, Stefan;

    2013-01-01

    Natural resource management requires approaches to understand and handle sources of uncertainty in future responses of complex systems to human activities. Here we present one such approach, the “biological ensemble modeling approach,” using the Eastern Baltic cod (Gadus morhua callarias) as an...... single-species to food web models. These models were analyzed using the “biological ensemble modeling approach” by which we (1) identified a key ecological mechanism explaining the differences in simulated cod responses between models, (2) disentangled the uncertainty caused by differences in ecological...... model assumptions from the statistical uncertainty of future climate, and (3) identified results common for the whole model ensemble. Species interactions greatly influenced the simulated response of cod to fishing and climate, as well as the degree to which the statistical uncertainty of climate...

  4. Effective potentials for atom-atom interaction at low temperatures

    OpenAIRE

    Gao, Bo

    2002-01-01

    We discuss the concept and design of effective atom-atom potentials that accurately describe any physical processes involving only states around the threshold. The existence of such potentials gives hope to a quantitative, and systematic, understanding of quantum few-atom and quantum many-atom systems at relatively low temperatures.

  5. Differential orientation effect in the neural response to interacting biological motion of two agents

    Directory of Open Access Journals (Sweden)

    Kakigi Ryusuke

    2009-04-01

    Full Text Available Abstract Background A recent behavioral study demonstrated that the meaningful interaction of two agents enhances the detection sensitivity of biological motion (BM, however, it remains unclear when and how the 'interaction' information of two agents is represented in our neural system. To clarify this point, we used magnetoencephalography and introduced a novel experimental technique to extract a neuromagnetic response relating to two-agent BM perception. We then investigated how this response was modulated by the interaction of two agents. In the present experiment, we presented two kinds of visual stimuli (interacting and non-interacting BM with two orientations (upright and inverted. Results We found a neuromagnetic response in the bilateral occipitotemporal region, on average 300 – 400 ms after the onset of a two-agent BM stimulus. This result showed that interhemispheric differences were apparent for the peak amplitudes. For the left hemisphere, the orientation effect was manifest when the two agents were made to interact, and the interaction effect was manifest when the stimulus was inverted. In the right hemisphere, the main effects of both orientation and interaction were significant, suggesting that the peak amplitude was attenuated when the visual stimulus was inverted or made to interact. Conclusion These results demonstrate that the 'interaction' information of two agents can affect the neural activities in the bilateral occipitotemporal region, on average 300 – 400 ms after the onset of a two-agent BM stimulus, however, the modulation was different between hemispheres: the left hemisphere is more concerned with dynamics, whereas the right hemisphere is more concerned with form information.

  6. A Review of the Biology, Culture, Exploitation and Utilization Potentials Seaweed Resources: Case Study in Nigeria

    Directory of Open Access Journals (Sweden)

    J.F.N. Abowei

    2011-04-01

    Full Text Available The importance of seaweeds cuts across various environmental, ecologic, socio-economic benefits and services as food for man, in the phycocolloids and expanding phycosupplement industries, as sink for excess carbon dioxide and excess nutrients; for sustainable energy generation and as fossil fuel substitutes. In view of this, seaweeds could become an important economic niche for Asian(Japan and China, Nigeria and other coastal African countries provided adequate research is undertaken in studying their diversity, biochemical compositions and potentials for culture in order to harness the numerous opportunities which can be derived. This article reviews the biological characteristics, potential products and uses, culture and transplantation, distribution and biodiversity, status of exploitation and conservation. Benefits of developing seaweed sector and challenges to the exploitation, culture and utilization of potential seaweed resources, aimed at unveiling the potentials in the utilization of seaweed in Nigeria and other interested countries.

  7. Phosphorus recycling potential assessment by a biological test applied to wastewater sludge.

    Science.gov (United States)

    Braak, Etienne; Auby, Sarah; Piveteau, Simon; Guilayn, Felipe; Daumer, Marie-Line

    2016-01-01

    Phosphorus (P) recycling as mineral fertilizer from wastewater activated sludge (WAS) depends on the amount that can be dissolved and separated from the organic matter before the final crystallization step. The aim of the biological phosphorus dissolution potential (BPDP) test developed here was to assess the maximum amount of P that could be biologically released from WAS prior that the liquid phase enters the recovery process. It was first developed for sludge combining enhanced biological phosphorus removal and iron chloride. Because carbohydrates are known to induce acidification during the first stage of anaerobic digestion, sucrose was used as a co-substrate. Best results were obtained after 24-48 h, without inoculum, with a sugar/sludge ratio of 0.5 gCOD/gVS and under strict anaerobic conditions. Up to 75% of the total phosphorus in sludge from a wastewater treatment plant combining enhanced biological phosphorus removal and iron chloride phosphorus removal could be dissolved. Finally, the test was applied to assess BPDP from different sludge using alum compounds for P removal. No dissolution was observed when alum polychloride was used and less than 20% when alum sulphate was used. In all the cases, comparison to chemical acidification showed that the biological process was a major contributor to P dissolution. The possibility to crystallize struvite was discussed from the composition of the liquids obtained. The BPDP will be used not only to assess the potential for phosphorus recycling from sludge, but also to study the influence of the co-substrates available for anaerobic digestion of sludge. PMID:26786893

  8. Mechanical and Biological Interactions of Implants with the Brain and Their Impact on Implant Design.

    Science.gov (United States)

    Prodanov, Dimiter; Delbeke, Jean

    2016-01-01

    Neural prostheses have already a long history and yet the cochlear implant remains the only success story about a longterm sensory function restoration. On the other hand, neural implants for deep brain stimulation are gaining acceptance for variety of disorders including Parkinsons disease and obsessive-compulsive disorder. It is anticipated that the progress in the field has been hampered by a combination of technological and biological factors, such as the limited understanding of the longterm behavior of implants, unreliability of devices, biocompatibility of the implants among others. While the field's understanding of the cell biology of interactions at the biotic-abiotic interface has improved, relatively little attention has been paid on the mechanical factors (stress, strain), and hence on the geometry that can modulate it. This focused review summarizes the recent progress in the understanding of the mechanisms of mechanical interaction between the implants and the brain. The review gives an overview of the factors by which the implants interact acutely and chronically with the tissue: blood-brain barrier (BBB) breach, vascular damage, micromotions, diffusion etc. We propose some design constraints to be considered in future studies. Aspects of the chronic cell-implant interaction will be discussed in view of the chronic local inflammation and the ways of modulating it. PMID:26903786

  9. Studies on pharmacokinetic drug interaction potential of vinpocetine

    Science.gov (United States)

    Background: Vinpocetine, a semi-synthetic derivative of vincamine, is a popular dietary supplement used for the treatment of several central nervous system related disorders. Despite its wide use, no pharmacokinetic drug interaction studies are reported in literature. Due to increasing use of dietar...

  10. The Stability of Icosahedral Cluster and the Range of Interaction Potential

    Institute of Scientific and Technical Information of China (English)

    DING Feng; WANG Jin-Lan; SHEN Wei-Feng; WANG Bao-Lin; LI Hui; WANG Guang-Hou

    2001-01-01

    The relation between the stability of icosahedral clusters and the range of interaction potential is discussed.We found that the stability of icosahedral clusters nay decrease with decreasing range of interaction potential. A simple formula about the critical number of icosahedral clusters and the range of interaction potential (M1/3c = A1 + A2r2eff)was proposed. The calculation of the stability of icosahedral fullerence molecular clusters shows that our idea is right.``

  11. Biological interactions in vitro of zinc oxide nanoparticles of different characteristics

    International Nuclear Information System (INIS)

    Zinc oxide nanoparticles (ZnO NPs) have recently received growing attention for various biomedical applications, including use as therapeutic or carrier for drug delivery and/or imaging. For the above applications, the NPs necessitate administration into the body leading to their systemic exposure. To better anticipate the safety, make risk assessment, and be able to interpret the future preclinical and clinical safety data, it is important to systematically understand the biological interaction of the NPs, the consequences of such interaction, and the mechanisms associated with the toxicity induction, with the important components with which the NPs are expected to be in contact after systemic exposure. In this context, we report here a detailed study on the biological interactions in vitro of the ZnO NPs with healthy human primary lymphocytes as these are the important immune components and the first systemic immune contact, and with the whole human blood. Additionally, the influence, if any, of the NPs shape (spheres and rods) on the biological interaction has been evaluated. The ZnO NPs caused toxicity (30% at 12.5 μg ml−1 spheres and 10.5 μg ml−1 rods; 50% at 22 μg ml−1 spheres and 19.5 μg ml−1 rods) to the lymphocytes at molecular and genetic level in a dose-dependent and shape-dependent manner, while the interaction consequences with the blood and blood components such as RBC, platelets was only dose-dependent and not shape-dependent. This is evident from the decreased RBC count due to increased %Hemolysis (5.3% in both the spheres- and rods-treated blood) and decreased platelet count due to increased %platelet aggregation (28% in spheres-treated and 33% in rods-treated platelet-rich plasma). Such in-depth understanding of the biological interaction of the NPs, the consequences, and the associated mechanisms in vitro could be expected to allow anticipating the NP safety for risk assessment and for interpretation of the preclinical and clinical

  12. Biological interactions in vitro of zinc oxide nanoparticles of different characteristics

    Science.gov (United States)

    Aula, Sangeetha; Lakkireddy, Samyuktha; AVN, Swamy; Kapley, Atya; Jamil, Kaiser; Rao Tata, Narasinga; Hembram, Kaliyan

    2014-09-01

    Zinc oxide nanoparticles (ZnO NPs) have recently received growing attention for various biomedical applications, including use as therapeutic or carrier for drug delivery and/or imaging. For the above applications, the NPs necessitate administration into the body leading to their systemic exposure. To better anticipate the safety, make risk assessment, and be able to interpret the future preclinical and clinical safety data, it is important to systematically understand the biological interaction of the NPs, the consequences of such interaction, and the mechanisms associated with the toxicity induction, with the important components with which the NPs are expected to be in contact after systemic exposure. In this context, we report here a detailed study on the biological interactions in vitro of the ZnO NPs with healthy human primary lymphocytes as these are the important immune components and the first systemic immune contact, and with the whole human blood. Additionally, the influence, if any, of the NPs shape (spheres and rods) on the biological interaction has been evaluated. The ZnO NPs caused toxicity (30% at 12.5 μg ml-1 spheres and 10.5 μg ml-1 rods; 50% at 22 μg ml-1 spheres and 19.5 μg ml-1 rods) to the lymphocytes at molecular and genetic level in a dose-dependent and shape-dependent manner, while the interaction consequences with the blood and blood components such as RBC, platelets was only dose-dependent and not shape-dependent. This is evident from the decreased RBC count due to increased %Hemolysis (5.3% in both the spheres- and rods-treated blood) and decreased platelet count due to increased %platelet aggregation (28% in spheres-treated and 33% in rods-treated platelet-rich plasma). Such in-depth understanding of the biological interaction of the NPs, the consequences, and the associated mechanisms in vitro could be expected to allow anticipating the NP safety for risk assessment and for interpretation of the preclinical and clinical safety

  13. Recent advances in the structural molecular biology of Ets transcription factors: interactions, interfaces and inhibition.

    Science.gov (United States)

    Cooper, Christopher D O; Newman, Joseph A; Gileadi, Opher

    2014-02-01

    The Ets family of eukaryotic transcription factors is based around the conserved Ets DNA-binding domain. Although their DNA-binding selectivity is biochemically and structurally well characterized, structures of homodimeric and ternary complexes point to Ets domains functioning as versatile protein-interaction modules. In the present paper, we review the progress made over the last decade to elucidate the structural mechanisms involved in modulation of DNA binding and protein partner selection during dimerization. We see that Ets domains, although conserved around a core architecture, have evolved to utilize a variety of interaction surfaces and binding mechanisms, reflecting Ets domains as dynamic interfaces for both DNA and protein interaction. Furthermore, we discuss recent advances in drug development for inhibition of Ets factors, and the roles structural biology can play in their future.

  14. Three "quantum" models of competition and cooperation in interacting biological populations and social groups

    CERN Document Server

    Vol, E D

    2012-01-01

    In present paper we propose the consistent statistical approach which appropriate for a number of models describing both behavior of biological populations and various social groups interacting with each other.The approach proposed based on the ideas of quantum theory of open systems (QTOS) and allows one to account explicitly both discreteness of a system variables and their fluctuations near mean values.Therefore this approach can be applied also for the description of small populations where standard dynamical methods are failed. We study in detail three typical models of interaction between populations and groups: 1) antagonistic struggle between two populations 2) cooperation (or, more precisely, obligatory mutualism) between two species 3) the formation of coalition between two feeble groups in their conflict with third one that is more powerful . The models considered in a sense are mutually complementary and include the most types of interaction between populations and groups. Besides this method can ...

  15. Highly homologous proteins exert opposite biological activities by using different interaction interfaces.

    Science.gov (United States)

    Amir, Anat Iosub; van Rosmalen, Martijn; Mayer, Guy; Lebendiker, Mario; Danieli, Tsafi; Friedler, Assaf

    2015-01-01

    We present a possible molecular basis for the opposite activity of two homologues proteins that bind similar ligands and show that this is achieved by fine-tuning of the interaction interface. The highly homologous ASPP proteins have opposite roles in regulating apoptosis: ASPP2 induces apoptosis while iASPP inhibits it. The ASPP proteins are regulated by an autoinhibitory interaction between their Ank-SH3 and Pro domains. We performed a detailed biophysical and molecular study of the Pro - Ank-SH3 interaction in iASPP and compared it to the interaction in ASPP2. We found that iASPP Pro is disordered and that the interaction sites are entirely different: iASPP Ank-SH3 binds iASPP Pro via its fourth Ank repeat and RT loop while ASPP2 Ank-SH3 binds ASPP2 Pro via its first Ank repeat and the n-src loop. It is possible that by using different moieties in the same interface, the proteins can have distinct and specific interactions resulting in differential regulation and ultimately different biological activities. PMID:26130271

  16. The influence of interactive technology on student performance in an Oklahoma secondary Biology I program

    Science.gov (United States)

    Feltman, Vallery

    Over the last decade growth in technologies available to teach students and enhance curriculum has become an important consideration in the educational system. The profile of today's secondary students have also been found to be quite different than those of the past. Their learning styles and preferences are issues that should be addressed by educators. With the growth and availability of new technologies students are increasingly expecting to use these as learning tools in their classrooms. This study investigates how interactive technology may impact student performance. This study specifically focuses on the use of the Apple Ipad in 4 Biology I classrooms. This study used an experimental mixed method design to examine how using Ipads for learning impacted student achievement, motivation to learn, and learning strategies. Qualitatively the study examined observed student behaviors and student perceptions regarding the use of interactive technologies. Data was analyzed using descriptive statistics, t-tests, 2-way ANOVAs, and qualitative analysis. Quantitatively the results revealed no significant difference between students who used the interactive technology to learn and those who did not. Qualitative data revealed behaviors indicative of being highly engaged with the subject matter and the development of critical thinking skills which may improve student performance. Student perceptions also revealed overall positive experiences with using interactive technology in the classroom. It is recommended that further studies be done to look at using interactive technologies for a longer period of time using multiple subjects areas. This would provide a more in-depth exploration of interactive technologies on student achievement.

  17. Highly homologous proteins exert opposite biological activities by using different interaction interfaces

    Science.gov (United States)

    Iosub Amir, Anat; van Rosmalen, Martijn; Mayer, Guy; Lebendiker, Mario; Danieli, Tsafi; Friedler, Assaf

    2015-07-01

    We present a possible molecular basis for the opposite activity of two homologues proteins that bind similar ligands and show that this is achieved by fine-tuning of the interaction interface. The highly homologous ASPP proteins have opposite roles in regulating apoptosis: ASPP2 induces apoptosis while iASPP inhibits it. The ASPP proteins are regulated by an autoinhibitory interaction between their Ank-SH3 and Pro domains. We performed a detailed biophysical and molecular study of the Pro - Ank-SH3 interaction in iASPP and compared it to the interaction in ASPP2. We found that iASPP Pro is disordered and that the interaction sites are entirely different: iASPP Ank-SH3 binds iASPP Pro via its fourth Ank repeat and RT loop while ASPP2 Ank-SH3 binds ASPP2 Pro via its first Ank repeat and the n-src loop. It is possible that by using different moieties in the same interface, the proteins can have distinct and specific interactions resulting in differential regulation and ultimately different biological activities.

  18. The importance of biological interactions for the vertical distribution of nematodes in a temperate ultra-dissipative sandy beach

    Science.gov (United States)

    Maria, Tatiana F.; Vanaverbeke, Jan; Esteves, André M.; De Troch, Marleen; Vanreusel, Ann

    2012-01-01

    This study of the vertical distribution of nematode communities in an ultra-dissipative sandy beach on the North Sea coast at De Panne, Belgium showed species-specific vertical migrations occurred over a tidal cycle. During the period of submersion, smaller deposit feeders were dominant at the subsurface, whereas large nematodes (originally classified as predators) were concentrated at the surface. The interstitial water content showed a weak correlation to the observed patterns and biological interactions among nematodes, such as predation and competition, which were measured through stable isotopes, also explained the observed segregation. The predator Enoplolaimus litoralis and its potential prey species did not co-exist in the same part of the sediment, suggesting avoidance of predation by prey species. In addition, the different prey species inhabited different subsurface layers, which can be explained by avoidance of competition for food. Stable isotope signatures further showed that the two major biological components of sandy beaches (macrofauna and meiofauna, including some species assumed to be predators) partly depend on microphytobenthos, demonstrating the importance of in situ primary producers in the diet of the fauna from ultra-dissipative sandy beaches. However, meiofauna and macrofauna do not seem to compete for these food sources. The combined examination of environmental and biological factors revealed the additional importance of the latter in controlling the vertical distribution of nematodes in environments that were previously assumed to be mainly physically controlled.

  19. Bubble-bubble interaction: A potential source of cavitation noise

    CERN Document Server

    Ida, Masato

    2009-01-01

    The interaction between microbubbles through pressure pulses has been studied to show that it can be a source of cavitation noise. A recent report demonstrated that the acoustic noise generated by a shrimp originates from the collapse of a cavitation bubble produced when the shrimp closes its snapper claw. The recorded acoustic signal contains a broadband noise that consists of positive and negative pulses, but a theoretical model for single bubbles fails to reproduce the negative ones. Using a nonlinear multibubble model we have shown here that the negative pulses can be explained by considering the interaction of microbubbles formed after the cavitation bubble has collapsed and fragmented: Positive pulses produced at the collapse of the microbubbles hit and impulsively compress neighboring microbubbles to generate reflected pulses whose amplitudes are negative. Discussing the details of the noise generation process, we have found that no negative pulses are generated if the internal pressure of the reflecti...

  20. Solution of the Dirac Equation for Potential Interaction

    OpenAIRE

    A. D. Alhaidari

    2002-01-01

    An effective approach for solving the three-dimensional Dirac equation for spherically symmetric local interactions, which we have introduced recently, is reviewed and consolidated. The merit of the approach is in producing Schrodinger-like equation for the spinor components that could simply be solved by correspondence with well-known exactly solvable non-relativistic problems. Taking the nonrelativistic limit will reproduce the nonrelativistic problem. The approach has been used successfull...

  1. In vitro interactions between Armillaria species and potential biocontrol fungi

    Directory of Open Access Journals (Sweden)

    Keča Nenad

    2009-01-01

    Full Text Available Interaction between Armillaria species and seven other fungi were tested in vitro. Tree antagonistic (Trichoderma viride, Trichotecium roseum and Penicillium sp. and four decaying (Hypholoma fasciculare¸ Hypholoma capnoides, Phlebiopsis gigantea, and Pleurotus ostreatus fungi were chosen for this study. The best results were noted for Trichoderma viride, because fungus was able to kill both mycelia and rhizomorphs of Armillaria species, while Hypholoma spp. inhibited both growth of Armillaria colonies and rhizomorph production.

  2. Gender differences, polypharmacy, and potential pharmacological interactions in the elderly

    OpenAIRE

    Carina Duarte Venturini; Paula Engroff; Luísa Scheer Ely; Luísa Faria de Araújo Zago; Guilherme Schroeter; Irenio Gomes; Geraldo Attilio De Carli,; Fernanda Bueno Morrone

    2011-01-01

    OBJECTIVE: This study aims to analyze pharmacological interactions among drugs taken by elderly patients and their age and gender differences in a population from Porto Alegre, Brazil. METHODS: We retrospectively analyzed the database provided by the Institute of Geriatric and Gerontology, Porto Alegre, Brazil. The database was composed of 438 elderly and includes information about the patients' disease, therapy regimens, utilized drugs. All drugs reported by the elderly patients were classif...

  3. Diagnostics of plasma-biological surface interactions in low pressure and atmospheric pressure plasmas

    Science.gov (United States)

    Ishikawa, Kenji; Hori, Masaru

    2014-08-01

    Mechanisms of plasma-surface interaction are required to understand in order to control the reactions precisely. Recent progress in atmospheric pressure plasma provides to apply as a tool of sterilization of contaminated foodstuffs. To use the plasma with safety and optimization, the real time in situ detection of free radicals - in particular dangling bonds by using the electron-spin-resonance (ESR) technique has been developed because the free radical plays important roles for dominantly biological reactions. First, the kinetic analysis of free radicals on biological specimens such as fungal spores of Penicillium digitatum interacted with atomic oxygen generated plasma electric discharge. We have obtained information that the in situ real time ESR signal from the spores was observed and assignable to semiquinone radical with a g-value of around 2.004 and a line width of approximately 5G. The decay of the signal was correlated with a link to the inactivation of the fungal spore. Second, we have studied to detect chemical modification of edible meat after the irradiation. Using matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF-MS) and ESR, signals give qualification results for chemical changes on edible liver meat. The in situ real-time measurements have proven to be a useful method to elucidate plasma-induced surface reactions on biological specimens.

  4. The fusion of heavy ions in an interaction potential model

    International Nuclear Information System (INIS)

    The paper contains the problems connected with fusion processes in heavy ions collision. Results of experimental fusion data for reactions: 9Be + 12C, 6Li + 28Si, 9Be + 28Si, 12C + 28Si, 12C + 16O and 16O + 16O are presented. Comparison of measured fusion cross sections with predictions of the fusion potential model have been made. The validity of this model for both light systems, like 9Be + 12C and heavy systems, like 35Cl + 62Ni, have been discussed. In conclusion, it should be stated that fusion cross sections could be correctly predicted by the potential model with a potential describing the elastic scattering data. (author)

  5. Theoretical studies of interaction potential and scattering cross section for He-CO system

    International Nuclear Information System (INIS)

    A new anisotropic interaction potential surface be fitted for He-CO system according to Maitland-Smith(MS) potential model. The scattering cross sections for the collision of CO with ground-state helium atom have been calculated by employing the fitting potential surface at collision energy of 27.7 meV. The results of the calculation indicate that the fitting potential surface can describe exactly the characteristic of interaction between CO and He. (authors)

  6. Studies on production and biological potential of prodigiosin by Serratia marcescens.

    Science.gov (United States)

    Suryawanshi, Rahul K; Patil, Chandrashekhar D; Borase, Hemant P; Salunke, Bipinchandra K; Patil, Satish V

    2014-07-01

    Efficacy of Serratia marcescens for pigment production and biological activity was investigated. Natural substrates like sweet potato, mahua flower extract (Madhuca latifolia L.), and sesam at different concentrations were taken. As a carbon source microorganism favored potato powder was followed by sesam and mannitol, and as nitrogen source casein hydrolysate was followed by yeast and malt extract. The effect of inorganic salts on pigment production was also studied. At final optimized composition of suitable carbon, nitrogen source, and trace materials and at suitable physiological conditions, prodigiosin production was 4.8 g L(-1). The isolated pigment showed antimicrobial activity against different pathogenic bacteria and fungi. Extracted pigment was characterized by spectroscopy, Fourier transform infrared (FTIR), and thin layer chromatography (TLC) which confirm production of biological compound prodigiosin. This study suggests that use of sweet potato powder and casein can be a potential alternative bioresource for commercial production of pigment prodigiosin. PMID:24781979

  7. Investigation of natural lipid-phenolic interactions on biological properties of virgin olive oil.

    Science.gov (United States)

    Alu'datt, Muhammad H; Rababah, Taha; Ereifej, Khalil; Gammoh, Sana; Alhamad, Mohammad N; Mhaidat, Nizar; Kubow, Stan; Johargy, Ayman; Alnaiemi, Ola J

    2014-12-10

    There is limited knowledge regarding the impact of naturally occurring lipid-phenolic interactions on the biological properties of phenolics in virgin olive oil. Free and bound phenolics were isolated via sequential methanolic extraction at 30 and 60 °C, and were identified and quantified using reversed phase high performance liquid chromatography, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), and gas chromatography. Decreased oleic acid concentrations and increased concentrations of palmitoleic acid, stearic, linoleic, and linolenic acids were observed in virgin olive oil after removal of free and bound lipid phenolic compounds. The presence of p-hydroxybenzoic acid and tyrosol bound to glycerides was determined via LC-MS/MS, which indicates natural lipid-phenolic interactions in virgin olive oil. Both free and lipid bound phenolic extracts exerted antiproliferative activities against the CRC1 and CRC5 colorectal cancer cell lines. The present work indicates that naturally occurring lipid-phenolic interactions can affect the biological properties of phenolics in virgin olive oil.

  8. Insects as test systems for assessing the potential role of microgravity in biological development and evolution

    Science.gov (United States)

    Vernós, I.; Carratalá, M.; González-Jurado, J.; Valverde, J. R.; Calleja, M.; Domingo, A.; Vinós, J.; Cervera, M.; Marco, R.

    Gravity and radiation are undoubtedly the two major environmental factors altered in space. Gravity is a weak force, which creates a permanent potential field acting on the mass of biological systems and their cellular components, strongly reduced in space flights. Developmental systems, particularly at very early stages, provide the larger cellular compartments known, where the effects of alterations in the size of the gravity vector on living organisms can be more effectively tested. The insects, one of the more highly evolved classes of animals in which early development occurs in a syncytial embryo, are systems particularly well suited to test these effects and the specific developmental mechanisms affected. Furthermore, they share some basic features such as small size, short life cycles, relatively high radio-resistance, etc. and show a diversity of developmental strategies and tempos advantageous in experiments of this type in space. Drosophila melanogaster, the current biological paradigm to study development, with so much genetic and evolutionary background available, is clearly the reference organism for these studies. The current evidence on the effects of the physical parameters altered in space flights on insect development indicate a surprising correlation between effects seen on the fast developing and relatively small Drosophila embryo and the more slowly developing and large Carausius morosus system. In relation to the issue of the importance of developmental and environmental constraints in biological evolution, still the missing link in current evolutionary thinking, insects and space facilities for long-term experiments could provide useful experimental settings where to critically assess how development and evolution may be interconnected. Finally, it has to be pointed out that since there are experimental data indicating a possible synergism between microgravity and space radiation, possible effects of space radiation should be taken into

  9. Fluorescent resonance energy transfer based detection of biological contaminants through hybrid quantum dot-quencher interactions.

    Science.gov (United States)

    Ramadurai, D; Norton, E; Hale, J; Garland, J W; Stephenson, L D; Stroscio, M A; Sivananthan, S; Kumar, A

    2008-06-01

    A nanoscale sensor employing fluorescent resonance energy transfer interactions between fluorescent quantum dots (QDs) and organic quencher molecules can be used for the multiplexed detection of biological antigens in solution. Detection occurs when the antigens to be detected displace quencher-labelled inactivated (or dead) antigens of the same type attached to QD-antibody complexes through equilibrium reactions. This unquenches the QDs, allowing detection to take place through the observation of photoluminescence in solution or through the fluorescence imaging of unquenched QD complexes trapped on filter surfaces. Multiplexing can be accomplished by using several different sizes of QDs, with each size QD labelled with an antibody for a different antigen, providing the ability to detect several types of antigens or biological contaminants simultaneously in near real-time with high specificity and sensitivity.

  10. Reduction theories elucidate the origins of complex biological rhythms generated by interacting delay-induced oscillations.

    Directory of Open Access Journals (Sweden)

    Ikuhiro Yamaguchi

    Full Text Available Time delay is known to induce sustained oscillations in many biological systems such as electroencephalogram (EEG activities and gene regulations. Furthermore, interactions among delay-induced oscillations can generate complex collective rhythms, which play important functional roles. However, due to their intrinsic infinite dimensionality, theoretical analysis of interacting delay-induced oscillations has been limited. Here, we show that the two primary methods for finite-dimensional limit cycles, namely, the center manifold reduction in the vicinity of the Hopf bifurcation and the phase reduction for weak interactions, can successfully be applied to interacting infinite-dimensional delay-induced oscillations. We systematically derive the complex Ginzburg-Landau equation and the phase equation without delay for general interaction networks. Based on the reduced low-dimensional equations, we demonstrate that diffusive (linearly attractive coupling between a pair of delay-induced oscillations can exhibit nontrivial amplitude death and multimodal phase locking. Our analysis provides unique insights into experimentally observed EEG activities such as sudden transitions among different phase-locked states and occurrence of epileptic seizures.

  11. ESL students learning biology: The role of language and social interactions

    Science.gov (United States)

    Jaipal, Kamini

    This study explored three aspects related to ESL students in a mainstream grade 11 biology classroom: (1) the nature of students' participation in classroom activities, (2) the factors that enhanced or constrained ESL students' engagement in social interactions, and (3) the role of language in the learning of science. Ten ESL students were observed over an eight-month period in this biology classroom. Data were collected using qualitative research methods such as participant observation, audio-recordings of lessons, field notes, semi-structured interviews, short lesson recall interviews and students' written work. The study was framed within sociocultural perspectives, particularly the social constructivist perspectives of Vygotsky (1962, 1978) and Wertsch (1991). Data were analysed with respect to the three research aspects. Firstly, the findings showed that ESL students' preferred and exhibited a variety of participation practices that ranged from personal-individual to socio-interactive in nature. Both personal-individual and socio-interactive practices appeared to support science and language learning. Secondly, the findings indicated that ESL students' engagement in classroom social interactions was most likely influenced by the complex interactions between a number of competing factors at the individual, interpersonal and community/cultural levels (Rogoff, Radziszewska, & Masiello, 1995). In this study, six factors that appeared to enhance or constrain ESL students' engagement in classroom social interactions were identified. These factors were socio-cultural factors, prior classroom practice, teaching practices, affective factors, English language proficiency, and participation in the research project. Thirdly, the findings indicated that language played a significant mediational role in ESL students' learning of science. The data revealed that the learning of science terms and concepts can be explained by a functional model of language that includes: (1

  12. Improved Interaction Potentials for Charged Residues in Proteins

    DEFF Research Database (Denmark)

    Kepp, Kasper Planeta

    2008-01-01

    Electrostatic interactions dominate the structure and free energy of biomolecules. To obtain accurate free energies involving charged groups from molecular simulations, OPLS-AA parameters have been reoptimized using Monte Carlo free energy perturbation. New parameters fit a self-consistent, exper......Electrostatic interactions dominate the structure and free energy of biomolecules. To obtain accurate free energies involving charged groups from molecular simulations, OPLS-AA parameters have been reoptimized using Monte Carlo free energy perturbation. New parameters fit a self......-consistent, experimental set of hydration free energies for acetate (Asp), propionate (Glu), 4-methylimidazolium (Hip), n-butylammonium (Lys), and n-propylguanidinium (Arg), all resembling charged residue side chains, including -carbons. It is shown that OPLS-AA free energies depend critically on the type of water model...... setup (MAEs of ca. 1 kcal/mol) and noise from simulations (ca. 1 kcal/mol). The latter error of ~1 kcal/mol contrasts MAEs from standard OPLS-AA of up to 13 kcal/mol for the entire series of charged residues or up to 5 kcal/mol for the cationic series Lys, Arg, and Hip. The new parameters can be used...

  13. Potential biological hazard of importance for HACCP plans in fresh fish processing

    Directory of Open Access Journals (Sweden)

    Baltić Milan Ž.

    2009-01-01

    Full Text Available The Hazard Analysis and Critical Control Point (HACCP system is scientifically based and focused on problem prevention in order to assure the produced food products are safe to consume. Prerequisite programs such as GMP (Good Manufacturing Practices, GHP (Good Hygienic Practices are an essential foundation for the development and implementation of successful HACCP plans. One of the preliminary tasks in the development of HACCP plan is to conduct a hazard analysis. The process of conducting a hazard analysis involves two stages. The first is hazard identification and the second stage is the HACCP team decision which potential hazards must be addressed in the HACCP plan. By definition, the HACCP concept covers all types of potential food safety hazards: biological, chemical and physical, whether they are naturally occurring in the food, contributed by the environment or generated by a mistake in the manufacturing process. In raw fish processing, potential significant biological hazards which are reasonably likely to cause illness of humans are parasites (Trematodae, Nematodae, Cestodae, bacteria (Salmonella, E. coli, Vibrio parahemolyticus, Vibrio vulnificus, Listeria monocytogenes, Clostridium botulinum, Staphyloccocus aureus, viruses (Norwalk virus, Entero virusesi, Hepatitis A, Rotovirus and bio-toxins. Upon completion of hazard analysis, any measure(s that are used to control the hazard(s should be described.

  14. Combining genomic sequencing methods to explore viral diversity and reveal potential virus-host interactions.

    Science.gov (United States)

    Chow, Cheryl-Emiliane T; Winget, Danielle M; White, Richard A; Hallam, Steven J; Suttle, Curtis A

    2015-01-01

    Viral diversity and virus-host interactions in oxygen-starved regions of the ocean, also known as oxygen minimum zones (OMZs), remain relatively unexplored. Microbial community metabolism in OMZs alters nutrient and energy flow through marine food webs, resulting in biological nitrogen loss and greenhouse gas production. Thus, viruses infecting OMZ microbes have the potential to modulate community metabolism with resulting feedback on ecosystem function. Here, we describe viral communities inhabiting oxic surface (10 m) and oxygen-starved basin (200 m) waters of Saanich Inlet, a seasonally anoxic fjord on the coast of Vancouver Island, British Columbia using viral metagenomics and complete viral fosmid sequencing on samples collected between April 2007 and April 2010. Of 6459 open reading frames (ORFs) predicted across all 34 viral fosmids, 77.6% (n = 5010) had no homology to reference viral genomes. These fosmids recruited a higher proportion of viral metagenomic sequences from Saanich Inlet than from nearby northeastern subarctic Pacific Ocean (Line P) waters, indicating differences in the viral communities between coastal and open ocean locations. While functional annotations of fosmid ORFs were limited, recruitment to NCBI's non-redundant "nr" database and publicly available single-cell genomes identified putative viruses infecting marine thaumarchaeal and SUP05 proteobacteria to provide potential host linkages with relevance to coupled biogeochemical cycling processes in OMZ waters. Taken together, these results highlight the power of coupled analyses of multiple sequence data types, such as viral metagenomic and fosmid sequence data with prokaryotic single cell genomes, to chart viral diversity, elucidate genomic and ecological contexts for previously unclassifiable viral sequences, and identify novel host interactions in natural and engineered ecosystems. PMID:25914678

  15. Combining genomic sequencing methods to explore viral diversity and reveal potential virus-host interactions.

    Science.gov (United States)

    Chow, Cheryl-Emiliane T; Winget, Danielle M; White, Richard A; Hallam, Steven J; Suttle, Curtis A

    2015-01-01

    Viral diversity and virus-host interactions in oxygen-starved regions of the ocean, also known as oxygen minimum zones (OMZs), remain relatively unexplored. Microbial community metabolism in OMZs alters nutrient and energy flow through marine food webs, resulting in biological nitrogen loss and greenhouse gas production. Thus, viruses infecting OMZ microbes have the potential to modulate community metabolism with resulting feedback on ecosystem function. Here, we describe viral communities inhabiting oxic surface (10 m) and oxygen-starved basin (200 m) waters of Saanich Inlet, a seasonally anoxic fjord on the coast of Vancouver Island, British Columbia using viral metagenomics and complete viral fosmid sequencing on samples collected between April 2007 and April 2010. Of 6459 open reading frames (ORFs) predicted across all 34 viral fosmids, 77.6% (n = 5010) had no homology to reference viral genomes. These fosmids recruited a higher proportion of viral metagenomic sequences from Saanich Inlet than from nearby northeastern subarctic Pacific Ocean (Line P) waters, indicating differences in the viral communities between coastal and open ocean locations. While functional annotations of fosmid ORFs were limited, recruitment to NCBI's non-redundant "nr" database and publicly available single-cell genomes identified putative viruses infecting marine thaumarchaeal and SUP05 proteobacteria to provide potential host linkages with relevance to coupled biogeochemical cycling processes in OMZ waters. Taken together, these results highlight the power of coupled analyses of multiple sequence data types, such as viral metagenomic and fosmid sequence data with prokaryotic single cell genomes, to chart viral diversity, elucidate genomic and ecological contexts for previously unclassifiable viral sequences, and identify novel host interactions in natural and engineered ecosystems.

  16. Combining genomic sequencing methods to explore viral diversity and reveal potential virus-host interactions

    Directory of Open Access Journals (Sweden)

    Cheryl-Emiliane Tien Chow

    2015-04-01

    Full Text Available Viral diversity and virus-host interactions in oxygen-starved regions of the ocean, also known as oxygen minimum zones (OMZs, remain relatively unexplored. Microbial community metabolism in OMZs alters nutrient and energy flow through marine food webs, resulting in biological nitrogen loss and greenhouse gas production. Thus, viruses infecting OMZ microbes have the potential to modulate community metabolism with resulting feedback on ecosystem function. Here, we describe viral communities inhabiting oxic surface (10m and oxygen-starved basin (200m waters of Saanich Inlet, a seasonally anoxic fjord on the coast of Vancouver Island, British Columbia using viral metagenomics and complete viral fosmid sequencing on samples collected between April 2007 and April 2010. Of 6459 open reading frames (ORFs predicted across all 34 viral fosmids, 77.6% (n=5010 had no homology to reference viral genomes. These fosmids recruited a higher proportion of viral metagenomic sequences from Saanich Inlet than from nearby northeastern subarctic Pacific Ocean (Line P waters, indicating differences in the viral communities between coastal and open ocean locations. While functional annotations of fosmid ORFs were limited, recruitment to NCBI’s non-redundant ‘nr’ database and publicly available single-cell genomes identified putative viruses infecting marine thaumarchaeal and SUP05 proteobacteria to provide potential host linkages with relevance to coupled biogeochemical cycling processes in OMZ waters. Taken together, these results highlight the power of coupled analyses of multiple sequence data types, such as viral metagenomic and fosmid sequence data with prokaryotic single cell genomes, to chart viral diversity, elucidate genomic and ecological contexts for previously unclassifiable viral sequences, and identify novel host interactions in natural and engineered ecosystems.

  17. MicroRNAs and potential target interactions in psoriasis

    DEFF Research Database (Denmark)

    Zibert, John Robert; Løvendorf, Marianne B.; Litman, Thomas;

    2010-01-01

    with NN. Based on the miRNA and mRNA profiles miR-21, -205, -221 and -222 were found to have the following potential mRNA targets in psoriatic skin: PDCD4, TPM1, P57, C-KIT, RTN4, SHIP2, TIMP3, RECK and NFIB. The identified target mRNAs were likely to be involved in cellular growth, proliferation...

  18. Serum and tissue PIVKA-II expression reflect the biological malignant potential of small hepatocellular carcinoma.

    Science.gov (United States)

    Tamano, Masaya; Sugaya, Hitoshi; Oguma, Motoo; Iijima, Makoto; Yoneda, Masashi; Murohisa, Toshimitsu; Kojima, Kazuo; Kuniyoshi, Toru; Majima, Yuichi; Hashimoto, Takashi; Terano, Akira

    2002-04-01

    A sensitive method for measuring the serum level of protein-induced by vitamin K absence or antagonist II (PIVKA-II) has become so widely available that it is now used for the clinical diagnosis of small hepatocellular carcinoma (HCC). It is known that serum PIVKA-II can be a prognostic indicator for HCC, but there have been no detailed investigations concerning the tissue expression of PIVKA-II. The present study assessed the relationship between serum or tissue PIVKA-II and the biological malignant potential of HCC. The subjects were 25 patients with histologically confirmed HCC, that were solitary and 3 cm or less in diameter. Tissue PIVKA-II was detected by immunostaining using MU-3 as the primary antibody. The biological malignant potential of the tumors was evaluated on the basis of the Ki-67 labeling index of HCC cells and the tumor arterial vascularity assesed by angiography and CO(2) enhanced ultrasonography. The recurrence-free period after treatment was also evaluated. Among the 25 patients, eight were positive for tissue PIVKA-II. Serum PIVKA-II levels were significantly higher in the tissue PIVKA-II-positive patients compared with the negative patients, but serum and tissue PIVKA-II expressions were not consistently parallel. Tumor cell proliferation was closely correlated with the tissue PIVKA-II expression, while the recurrence-free period was correlated with the serum PIVKA-II level. Tumor arterial vascularity showed a strong correlation with the expression of both serum and tissue PIVKA-II. In conclusion, serum and tissue PIVKA-II expression reflect the biological malignant potential of HCC and thus may be useful indicators for the prognosis of small HCC.

  19. A MOLECULAR-DYNAMICS STUDY OF B2O3 GLASS USING DIFFERENT INTERACTION POTENTIALS

    NARCIS (Netherlands)

    VERHOEF, AH; DENHARTOG, HW

    1992-01-01

    Molecular dynamics calculations of B2O3 glass were carried out, using seven different interaction potential schemes. Two-body Born-Mayer-Huggins potentials and in some samples a[so three-body bond-angle interactions were applied. Structural and dynamical properties of the simulated systems were eval

  20. On critical stability of three quantum charges interacting through delta potentials

    DEFF Research Database (Denmark)

    Cornean, Horia; Duclos, Pierre; Ricaud, Benjamin

    We consider three one dimensional quantum, charged and spinless particles interacting through delta potentials. We derive sufficient conditions which guarantee the existence of at least one bound state.......We consider three one dimensional quantum, charged and spinless particles interacting through delta potentials. We derive sufficient conditions which guarantee the existence of at least one bound state....

  1. Importance of biological systems in industrial waste treatment potential application to the space station

    Science.gov (United States)

    Revis, Nathaniel; Holdsworth, George

    1990-01-01

    In addition to having applications for waste management issues on planet Earth, microbial systems have application in reducing waste volumes aboard spacecraft. A candidate for such an application is the space station. Many of the planned experiments generate aqueous waste. To recycle air and water the contaminants from previous experiments must be removed before the air and water can be used for other experiments. This can be achieved using microorganisms in a bioreactor. Potential bioreactors (inorganics, organics, and etchants) are discussed. Current technologies that may be applied to waste treatment are described. Examples of how biological systems may be used in treating waste on the space station.

  2. Biological characteristics of dengue virus and potential targets for drug design

    Institute of Scientific and Technical Information of China (English)

    Rui-feng Qi; Ling Zhang; Cheng-wu Chi

    2008-01-01

    Dengue infection is a major cause of morbidity in tropical and subtropical regions, bringing nearly 40% of the world population at risk and causing more than 20,000 deaths per year. But there is neither a vaccine for dengue disease nor antiviral drugs to treat the infection. In recent years, dengue infection has been particularly prevalent in India, Southeast Asia, Brazil, and Guangdong Province, China. In this article, we present a brief summary of the biological characteristics of dengue virus and associated flaviviruses, and outline the progress on studies of vaccines and drugs based on potential targets of the dengue virus.

  3. Biology-environment interaction and evocative biology-environment correlation: contributions of harsh discipline and parental psychopathology to problem adolescent behaviors.

    Science.gov (United States)

    Riggins-Caspers, Kristin M; Cadoret, Remi J; Knutson, John F; Langbehn, Douglas

    2003-05-01

    Using an adoption paradigm, the Bioecological Model of development proposed by Bronfenbrenner and Ceci in 1994 was tested by concurrently modeling for biology-environment interaction and evocative biology-environment correlation. A sample of 150 adult adoptees (ages, 18-45 years) provided retrospective reports of harsh adoptive parent discipline, which served as the environmental independent variables. Birth parent psychopathology served as the biological predictor. The dependent variables were retrospective adoptee and adoptive parent reports on adolescent aggressive and conduct-disordered behaviors. Finally, adoptees were classified as experiencing contextual environmental risk using the presence of two or more adverse factors in the adoptive home (e.g., adoptive parent psychopathology) as the cutoff. The contextual environment was found to moderate the biological process of evocative biology-environment correlation, providing empirical support for the Bronfenbrenner and Ceci (1994) Bioecological Model.

  4. Collaborative Research. Fundamental Science of Low Temperature Plasma-Biological Material Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Graves, David Barry [Univ. California, Berkeley, CA (United States); Oehrlein, Gottlieb [Univ. of Maryland, College Park, MD (United States)

    2014-09-01

    Low temperature plasma (LTP) treatment of biological tissue is a promising path toward sterilization of bacteria due to its versatility and ability to operate under well-controlled and relatively mild conditions. The present collaborative research of an interdisciplinary team of investigators at University of Maryland, College Park (UMD), and University of California, Berkeley (UCB) focused on establishing our knowledge based with regard to low temperature plasma-induced chemical modifications in biomolecules that result in inactivation due to various plasma species, including ions, reactive radicals, and UV/VUV photons. The overall goals of the project were to identify and quantify the mechanisms by which low and atmospheric pressure plasma deactivates endotoxic biomolecules. Additionally, we wanted to understand the mechanism by which atmospheric pressure plasmas (APP) modify surfaces and how these modifications depend on the interaction of APP with the environment. Various low pressure plasma sources, a vacuum beam system and several atmospheric pressure plasma sources were used to accomplish this. In our work we elucidated for the first time the role of ions, VUV photons and radicals in biological deactivation of representative biomolecules, both in a UHV beam system and an inductively coupled, low pressure plasma system, and established the associated atomistic biomolecule changes. While we showed that both ions and VUV photons can be very efficient in deactivation of biomolecules, significant etching and/or deep modification (~200 nm) accompanied these biological effects. One of the most important findings in this work is the significant radical-induced deactivation and surface modification can occur with minimal etching. However, if radical fluxes and corresponding etch rates are relatively high, for example at atmospheric pressure, endotoxic biomolecule film inactivation may require near-complete removal of the film. These findings motivated further work at

  5. Proteomic dissection of biological pathways/processes through profiling protein-protein interaction networks

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Cellular functions, either under the normal or pathological conditions or under different stresses, are the results of the coordinated action of multiple proteins interacting in macromolecular complexes or assemblies. The precise determination of the specific composition of protein complexes, especially using scalable and high-throughput methods, represents a systematic approach toward revealing particular cellular biological functions. In this regard, the direct profiling protein-protein interactions (PPIs) represent an efficient way to dissect functional pathways for revealing novel protein functions. In this review, we illustrate the technological evolution for the large-scale and precise identification of PPIs toward higher physiologically relevant accuracy. These techniques aim at improving the efficiency of complex pull-down, the signal specificity and accuracy in distinguishing specific PPIs, and the accuracy of identifying physiological relevant PPIs. A newly developed streamline proteomic approach for mapping the binary relationship of PPIs in a protein complex is introduced.

  6. Technological Dangers and the Potential of Human-Robot Interaction

    DEFF Research Database (Denmark)

    Nørskov, Marco

    2016-01-01

    The ethical debate on social robotics has become one of the cutting edge topics of our time. When it comes to both academic and non-academic debates, the methodological framework is, with few exceptions, typically and tacitly grounded in an us-versus-them perspective. It is as though we were...... technological dangers and opportunities. Finally, aiming for the very limits of the theory, I discuss the contours of a praxis facilitating being-with-robots beyond conceptualization. Basically, this mode of being, pertaining to non-technological HRI, bypasses Heidegger’s warnings, and potentially facilitates...

  7. Physical-chemical characterization of nanoparticles in relevant biological environments and their interactions with the cell surface

    OpenAIRE

    Di Silvio, Desire

    2015-01-01

    Nanoparticles (NPs) are versatile tools for nanomedicine and tuning features such as material, size and charge, imaging and targeting can be accomplished. However, NPs behaviour in vivo is modified upon interaction with the biological matter and formation of a protein corona (PC) coating the NP. The PC determines the NP biological identity and it is the ultimate interface with the surrounding environment. Therefore, a deep characterization of the NPs in biological media is important to predic...

  8. [Glanders--a potential disease for biological warfare in humans and animals].

    Science.gov (United States)

    Lehavi, Ofer; Aizenstien, Orna; Katz, Lior H; Hourvitz, Ariel

    2002-05-01

    Infection with Burkholderia mallei (formerly Pseudomonas mallei) can cause a subcutaneous infection known as "farcy" or can disseminate to condition known as Glanders. It is primarily a disease affecting horses, donkeys and mules. In humans, Glanders can produce four types of disease: localized form, pulmonary form, septicemia, and chronic form. Necrosis of the tracheobronchial tree and pustular skin lesions characterize acute infection with B. mallei. Other symptoms include febrile pneumonia, if the organism was inhaled, or signs of sepsis and multiple abscesses, if the skin was the port of entry. Glanders is endemic in Africa, Asia, the Middle East, and Central and South America. Glanders has low contiguous potential, but because of the efficacy of aerosolized dissemination and the lethal nature of the disease, B. mallei was considered a candidate for biological warfare. During World War I, Glanders was believed to have been spread to infect large numbers of Russian horses and mules on the Eastern front. The Japanese infected horses, civilians and prisoners of war during World War II. The USA and the Soviet Union have shown interest in B. mallei in their biological warfare program. The treatment is empiric and includes mono or poly-therapy with Ceftazidime, Sulfadiazine, Trimethoprim + Sulfamethoxazol, Gentamicin, Imipenem etc. Aggressive control measures essentially eliminated Glanders from the west. However, with the resurgent concern about biological warfare, B. mallei is now being studied in a few laboratories worldwide. This review provides an overview of the disease and presents the only case reported in the western world since 1949.

  9. Clinical treatment adherence of health care workers and students exposed to potentially infectious biological material

    Directory of Open Access Journals (Sweden)

    Maria Cristina Mendes de Almeida

    2015-04-01

    Full Text Available OBJECTIVE To assess adherence to clinical appointments by health care workers (HCW and students who suffered accidents with potentially infectious biological material. METHOD A retrospective cross-sectional study that assessed clinical records of accidents involving biological material between 2005 and 2010 in a specialized unit. RESULTS A total of 461 individuals exposed to biological material were treated, of which 389 (84.4% were HCWs and 72 (15.6% students. Of the 461 exposed individuals, 307 (66.6% attended a follow-up appointment. Individuals who had suffered an accident with a known source patient were 29 times more likely to show up to their scheduled follow-up appointments (OR: 29.98; CI95%: 16.09-55.83. CONCLUSION The predictor in both univariate and multivariate analyses for adherence to clinical follow-up appointment was having a known source patient with nonreactive serology for the human immunodeficiency virus and/or hepatitis B and C.

  10. Cardiocladius oliffi (Diptera: Chironomidae as a potential biological control agent against Simulium squamosum (Diptera: Simuliidae

    Directory of Open Access Journals (Sweden)

    Wilson Michael D

    2009-04-01

    Full Text Available Abstract Background The control of onchocerciasis in the African region is currently based mainly on the mass drug administration of ivermectin. Whilst this has been found to limit morbidity, it does not stop transmission. In the absence of a macrofilaricide, there is a need for an integrated approach for disease management, which includes vector control. Vector control using chemical insecticides is expensive to apply, and therefore the use of other measures such as biological control agents is needed. Immature stages of Simulium squamosum, reared in the laboratory from egg masses collected from the field at Boti Falls and Huhunya (River Pawnpawn in Ghana, were observed to be attacked and fed upon by larvae of the chironomid Cardiocladius oliffi Freeman, 1956 (Diptera: Chironomidae. Methods Cardiocladius oliffi was successfully reared in the rearing system developed for S. damnosum s.l. and evaluated for its importance as a biological control agent in the laboratory. Results Even at a ratio of one C. oliffi to five S. squamosum, they caused a significant decrease in the number of adult S. squamosum emerging from the systems (treatments. Predation was confirmed by the amplification of Simulium DNA from C. oliffi observed to have fed on S. squamosum pupae. The study also established that the chironomid flies could successfully complete their development on a fish food diet only. Conclusion Cardiocladius oliffi has been demonstrated as potential biological control agent against S. squamosum.

  11. Estimating the Effects of Habitat and Biological Interactions in an Avian Community.

    Directory of Open Access Journals (Sweden)

    Robert M Dorazio

    Full Text Available We used repeated sightings of individual birds encountered in community-level surveys to investigate the relative roles of habitat and biological interactions in determining the distribution and abundance of each species. To analyze these data, we developed a multispecies N-mixture model that allowed estimation of both positive and negative correlations between abundances of different species while also estimating the effects of habitat and the effects of errors in detection of each species. Using a combination of single- and multispecies N-mixture modeling, we examined for each species whether our measures of habitat were sufficient to account for the variation in encounter histories of individual birds or whether other habitat variables or interactions with other species needed to be considered. In the community that we studied, habitat appeared to be more influential than biological interactions in determining the distribution and abundance of most avian species. Our results lend support to the hypothesis that abundances of forest specialists are negatively affected by forest fragmentation. Our results also suggest that many species were associated with particular types of vegetation as measured by structural attributes of the forests. The abundances of 6 of the 73 species observed in our study were strongly correlated. These species included large birds (American Crow (Corvus brachyrhynchos and Red-winged Blackbird (Agelaius phoeniceus that forage on the ground in open habitats and small birds (Red-eyed Vireo (Vireo olivaceus, House Wren (Troglodytes aedon, Hooded Warbler (Setophaga citrina, and Prairie Warbler (Setophaga discolor that are associated with dense shrub cover. Species abundances were positively correlated within each size group and negatively correlated between groups. Except for the American Crow, which preys on eggs and nestlings of small song birds, none of the other 5 species is known to display direct interactions, so we

  12. Bioactive protein-based nanofibers interact with intestinal biological components resulting in transepithelial permeation of a therapeutic protein.

    Science.gov (United States)

    Stephansen, Karen; García-Díaz, María; Jessen, Flemming; Chronakis, Ioannis S; Nielsen, Hanne Mørck

    2015-11-10

    Proteins originating from natural sources may constitute a novel type of material for use in drug delivery. However, thorough understanding of the behavior and effects of such a material when processed into a matrix together with a drug is crucial prior to further development into a drug product. In the present study the potential of using bioactive electrospun fish sarcoplasmic proteins (FSP) as a carrier matrix for small therapeutic proteins was demonstrated in relation to the interactions with biological components of the intestinal tract. The inherent structural and chemical properties of FSP as a biomaterial facilitated interactions with cells and enzymes found in the gastrointestinal tract and displayed excellent biocompatibility. More specifically, insulin was efficiently encapsulated into FSP fibers maintaining its conformation, and subsequent controlled release was obtained in simulated intestinal fluid. The encapsulation of insulin into FSP fibers provided protection against chymotrypsin degradation, and resulted in an increase in insulin transport to around 12% without compromising the cellular viability. This increased transport was driven by interactions upon contact between the nanofibers and the Caco-2 cell monolayer leading to the opening of the tight junction proteins. Overall, electrospun FSP may constitute a novel material for oral delivery of biopharmaceuticals. PMID:26320547

  13. No enhancement of the localization length for two interacting particles in a random potential

    OpenAIRE

    Römer, R. A.; Schreiber, M.

    1998-01-01

    We study two interacting particles in a random potential chain by means of the transfer matrix method. The dependence of the two-particle localization length $\\lambda_2$ on disorder and interaction strength is investigated. Our results demonstrate that the recently proposed enhancement of $\\lambda_2$ as compared to the results for single particles is entirely due to the finite size of the systems considered. This is shown for a Hubbard-like onsite interaction and also a long-range interaction.

  14. Novel factors in the pathogenesis of psoriasis and potential drug candidates are found with systems biology approach.

    Directory of Open Access Journals (Sweden)

    Máté Manczinger

    Full Text Available Psoriasis is a multifactorial inflammatory skin disease characterized by increased proliferation of keratinocytes, activation of immune cells and susceptibility to metabolic syndrome. Systems biology approach makes it possible to reveal novel important factors in the pathogenesis of the disease. Protein-protein, protein-DNA, merged (containing both protein-protein and protein-DNA interactions and chemical-protein interaction networks were constructed consisting of differentially expressed genes (DEG between lesional and non-lesional skin samples of psoriatic patients and/or the encoded proteins. DEGs were determined by microarray meta-analysis using MetaOMICS package. We used STRING for protein-protein, CisRED for protein-DNA and STITCH for chemical-protein interaction network construction. General network-, cluster- and motif-analysis were carried out in each network. Many DEG-coded proteins (CCNA2, FYN, PIK3R1, CTGF, F3 and transcription factors (AR, TFDP1, MEF2A, MECOM were identified as central nodes, suggesting their potential role in psoriasis pathogenesis. CCNA2, TFDP1 and MECOM might play role in the hyperproliferation of keratinocytes, whereas FYN may be involved in the disturbed immunity in psoriasis. AR can be an important link between inflammation and insulin resistance, while MEF2A has role in insulin signaling. A controller sub-network was constructed from interlinked positive feedback loops that with the capability to maintain psoriatic lesional phenotype. Analysis of chemical-protein interaction networks detected 34 drugs with previously confirmed disease-modifying effects, 23 drugs with some experimental evidences, and 21 drugs with case reports suggesting their positive or negative effects. In addition, 99 unpublished drug candidates were also found, that might serve future treatments for psoriasis.

  15. Symmetry adapted cluster-configuration interaction calculation of the photoelectron spectra of famous biological active steroids

    Science.gov (United States)

    Abyar, Fatemeh; Farrokhpour, Hossein

    2014-11-01

    The photoelectron spectra of some famous steroids, important in biology, were calculated in the gas phase. The selected steroids were 5α-androstane-3,11,17-trione, 4-androstane-3,11,17-trione, cortisol, cortisone, corticosterone, dexamethasone, estradiol and cholesterol. The calculations were performed employing symmetry-adapted cluster/configuration interaction (SAC-CI) method using the 6-311++G(2df,pd) basis set. The population ratios of conformers of each steroid were calculated and used for simulating the photoelectron spectrum of steroid. It was found that more than one conformer contribute to the photoelectron spectra of some steroids. To confirm the calculated photoelectron spectra, they compared with their corresponding experimental spectra. There were no experimental gas phase Hesbnd I photoelectron spectra for some of the steroids of this work in the literature and their calculated spectra can show a part of intrinsic characteristics of this molecules in the gas phase. The canonical molecular orbitals involved in the ionization of each steroid were calculated at the HF/6-311++g(d,p) level of theory. The spectral bands of each steroid were assigned by natural bonding orbital (NBO) calculations. Knowing the electronic structures of steroids helps us to understand their biological activities and find which sites of steroid become active when a modification is performing under a biological pathway.

  16. Secondary metabolites as potential cancer therapeutic leads : : synthesis and chemical biology of Englerin A and Fusarisetin A

    OpenAIRE

    Caro-Diaz, Eduardo J.E.

    2014-01-01

    Secondary metabolites generated from natural sources such as microbes, fungi, marine fauna and other microorganism have proven to represent a microcosm of chemical diversity and therefore a great source of novel phamacophoric structures. It is without question that nature in its long biological and chemical evolution has gifted us with beautiful molecular architectures with equally important biological function to provide leads into new and potentially useful biologically active molecules. As...

  17. Chemical Structure-Biological Activity Models for Pharmacophores' 3D-Interactions.

    Science.gov (United States)

    Putz, Mihai V; Duda-Seiman, Corina; Duda-Seiman, Daniel; Putz, Ana-Maria; Alexandrescu, Iulia; Mernea, Maria; Avram, Speranta

    2016-01-01

    Within medicinal chemistry nowadays, the so-called pharmaco-dynamics seeks for qualitative (for understanding) and quantitative (for predicting) mechanisms/models by which given chemical structure or series of congeners actively act on biological sites either by focused interaction/therapy or by diffuse/hazardous influence. To this aim, the present review exposes three of the fertile directions in approaching the biological activity by chemical structural causes: the special computing trace of the algebraic structure-activity relationship (SPECTRAL-SAR) offering the full analytical counterpart for multi-variate computational regression, the minimal topological difference (MTD) as the revived precursor for comparative molecular field analyses (CoMFA) and comparative molecular similarity indices analysis (CoMSIA); all of these methods and algorithms were presented, discussed and exemplified on relevant chemical medicinal systems as proton pump inhibitors belonging to the 4-indolyl,2-guanidinothiazole class of derivatives blocking the acid secretion from parietal cells in the stomach, the 1-[(2-hydroxyethoxy)-methyl]-6-(phenylthio)thymine congeners' (HEPT ligands) antiviral activity against Human Immunodeficiency Virus of first type (HIV-1) and new pharmacophores in treating severe genetic disorders (like depression and psychosis), respectively, all involving 3D pharmacophore interactions. PMID:27399692

  18. Chemical Structure-Biological Activity Models for Pharmacophores’ 3D-Interactions

    Directory of Open Access Journals (Sweden)

    Mihai V. Putz

    2016-07-01

    Full Text Available Within medicinal chemistry nowadays, the so-called pharmaco-dynamics seeks for qualitative (for understanding and quantitative (for predicting mechanisms/models by which given chemical structure or series of congeners actively act on biological sites either by focused interaction/therapy or by diffuse/hazardous influence. To this aim, the present review exposes three of the fertile directions in approaching the biological activity by chemical structural causes: the special computing trace of the algebraic structure-activity relationship (SPECTRAL-SAR offering the full analytical counterpart for multi-variate computational regression, the minimal topological difference (MTD as the revived precursor for comparative molecular field analyses (CoMFA and comparative molecular similarity indices analysis (CoMSIA; all of these methods and algorithms were presented, discussed and exemplified on relevant chemical medicinal systems as proton pump inhibitors belonging to the 4-indolyl,2-guanidinothiazole class of derivatives blocking the acid secretion from parietal cells in the stomach, the 1-[(2-hydroxyethoxy-methyl]-6-(phenylthiothymine congeners’ (HEPT ligands antiviral activity against Human Immunodeficiency Virus of first type (HIV-1 and new pharmacophores in treating severe genetic disorders (like depression and psychosis, respectively, all involving 3D pharmacophore interactions.

  19. Chemical Structure-Biological Activity Models for Pharmacophores’ 3D-Interactions

    Science.gov (United States)

    Putz, Mihai V.; Duda-Seiman, Corina; Duda-Seiman, Daniel; Putz, Ana-Maria; Alexandrescu, Iulia; Mernea, Maria; Avram, Speranta

    2016-01-01

    Within medicinal chemistry nowadays, the so-called pharmaco-dynamics seeks for qualitative (for understanding) and quantitative (for predicting) mechanisms/models by which given chemical structure or series of congeners actively act on biological sites either by focused interaction/therapy or by diffuse/hazardous influence. To this aim, the present review exposes three of the fertile directions in approaching the biological activity by chemical structural causes: the special computing trace of the algebraic structure-activity relationship (SPECTRAL-SAR) offering the full analytical counterpart for multi-variate computational regression, the minimal topological difference (MTD) as the revived precursor for comparative molecular field analyses (CoMFA) and comparative molecular similarity indices analysis (CoMSIA); all of these methods and algorithms were presented, discussed and exemplified on relevant chemical medicinal systems as proton pump inhibitors belonging to the 4-indolyl,2-guanidinothiazole class of derivatives blocking the acid secretion from parietal cells in the stomach, the 1-[(2-hydroxyethoxy)-methyl]-6-(phenylthio)thymine congeners’ (HEPT ligands) antiviral activity against Human Immunodeficiency Virus of first type (HIV-1) and new pharmacophores in treating severe genetic disorders (like depression and psychosis), respectively, all involving 3D pharmacophore interactions. PMID:27399692

  20. Removal of disinfection by-products formation potential by biologically intensified process

    Institute of Scientific and Technical Information of China (English)

    AN Dong; LI Wei-guang; CUI Fu-yi; HE Xin; ZHANG Jin-song

    2005-01-01

    The removal of disinfection by-products formation potential(DBPFP) in artificially intensified biological activated carbon(IBAC) process which is developed on the basis of traditional ozone granular activated carbon was evaluated. By IBAC removals of 31% and 68% for THMFP and HAAFP were obtained respectively. Under identical conditions, the removals of the same substances were 4% and 32% respectively only by the granular activated carbon(GAC) process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. A clear linear correlation ( R2 = 0.9562 and R2 = 0.9007) between DOC HAAFP removal rate and Empty Bed Contact Time(EBCT) of IBAC process was observed, while that between THMFP removal rate and EBCT of GAC was R2 = 0.9782. In addition certain linear correlations between THMFP, HAAFP and UV254 ( R2 = 0.855 and R2 = 0.7702) were found for the treated water. For IBAC process there are also more advantages such as long backwashing cycle time, low backwashing intensity and prolonging activated carbon lifetime and so on.

  1. Evaluation of a Potential Clinical Interaction between Ceftriaxone and Calcium▿

    Science.gov (United States)

    Steadman, Emily; Raisch, Dennis W.; Bennett, Charles L.; Esterly, John S.; Becker, Tischa; Postelnick, Michael; McKoy, June M.; Trifilio, Steve; Yarnold, Paul R.; Scheetz, Marc H.

    2010-01-01

    In April 2009, the FDA retracted a warning asserting that ceftriaxone and intravenous calcium products should not be coadministered to any patient to prevent precipitation events leading to end-organ damage. Following that announcement, we sought to evaluate if the retraction was justified. A search of the FDA Adverse Event Reporting System was conducted to identify any ceftriaxone-calcium interactions that resulted in serious adverse drug events. Ceftazidime-calcium was used as a comparator agent. One hundred four events with ceftriaxone-calcium and 99 events with ceftazidime-calcium were identified. Adverse drug events were recorded according to the listed description of drug involvement (primary or secondary suspect) and were interpreted as probable, possible, unlikely, or unrelated. For ceftriaxone-calcium-related adverse events, 7.7% and 20.2% of the events were classified as probable and possible for embolism, respectively. Ceftazidime-calcium resulted in fewer probable embolic events (4%) but more possible embolic events (30.3%). Among cases that considered ceftriaxone or ceftazidime and calcium as the primary or secondary drug, one case was classified as a probable embolic event. That patient received ceftriaxone-calcium and died, although an attribution of causality was not possible. Our analysis suggests a lack of support for the occurrence of ceftriaxone-calcium precipitation events in adults. The results of the current analysis reinforce the revised FDA recommendations suggesting that patients >28 days old may receive ceftriaxone and calcium sequentially and provide a transparent and reproducible methodology for such evaluations. PMID:20086152

  2. Taurolidine antiadhesive properties on interaction with E. coli; its transformation in biological environment and interaction with bacteria cell wall.

    Science.gov (United States)

    Caruso, Francesco; Darnowski, James W; Opazo, Cristian; Goldberg, Alexander; Kishore, Nina; Agoston, Elin S; Rossi, Miriam

    2010-01-28

    The taurine amino-acid derivative, taurolidine, bis-(1,1-dioxoperhydro-1,2,4-thiabiazinyl-4)methane, shows broad antibacterial action against gram-positive and gram-negative bacteria, mycobacteria and some clinically relevant fungi. It inhibits, in vitro, the adherence of Escherichia coli and Staphylococcus aureus to human epithelial and fibroblast cells. Taurolidine is unstable in aqueous solution and breaks down into derivatives which are thought to be responsible for the biological activity. To understand the taurolidine antibacterial mechanism of action, we provide the experimental single crystal X-ray diffraction results together with theoretical methods to characterize the hydrolysis/decomposition reactions of taurolidine. The crystal structure features two independent molecules linked through intermolecular H-bonds with one of them somewhat positively charged. Taurolidine in a biological environment exists in equilibrium with taurultam derivatives and this is described theoretically as a 2-step process without an energy barrier: formation of cationic taurolidine followed by a nucleophilic attack of O(hydroxyl) on the exocyclic C(methylene). A concerted mechanism describes the further hydrolysis of the taurolidine derivative methylol-taurultam. The interaction of methylol-taurultam with the diaminopimelic NH(2) group in the E. coli bacteria cell wall (peptidoglycan) has a negative DeltaG value (-38.2 kcal/mol) but a high energy barrier (45.8 kcal/mol) suggesting no reactivity. On the contrary, taurolidine docking into E. coli fimbriae protein, responsible for bacteria adhesion to the bladder epithelium, shows it has higher affinity than mannose (the natural substrate), whereas methylol-taurultam and taurultam are less tightly bound. Since taurolidine is readily available because it is administered in high doses after peritonitis surgery, it may successfully compete with mannose explaining its effectiveness against bacterial infections at laparoscopic lesions.

  3. Taurolidine antiadhesive properties on interaction with E. coli; its transformation in biological environment and interaction with bacteria cell wall.

    Directory of Open Access Journals (Sweden)

    Francesco Caruso

    Full Text Available The taurine amino-acid derivative, taurolidine, bis-(1,1-dioxoperhydro-1,2,4-thiabiazinyl-4methane, shows broad antibacterial action against gram-positive and gram-negative bacteria, mycobacteria and some clinically relevant fungi. It inhibits, in vitro, the adherence of Escherichia coli and Staphylococcus aureus to human epithelial and fibroblast cells. Taurolidine is unstable in aqueous solution and breaks down into derivatives which are thought to be responsible for the biological activity. To understand the taurolidine antibacterial mechanism of action, we provide the experimental single crystal X-ray diffraction results together with theoretical methods to characterize the hydrolysis/decomposition reactions of taurolidine. The crystal structure features two independent molecules linked through intermolecular H-bonds with one of them somewhat positively charged. Taurolidine in a biological environment exists in equilibrium with taurultam derivatives and this is described theoretically as a 2-step process without an energy barrier: formation of cationic taurolidine followed by a nucleophilic attack of O(hydroxyl on the exocyclic C(methylene. A concerted mechanism describes the further hydrolysis of the taurolidine derivative methylol-taurultam. The interaction of methylol-taurultam with the diaminopimelic NH(2 group in the E. coli bacteria cell wall (peptidoglycan has a negative DeltaG value (-38.2 kcal/mol but a high energy barrier (45.8 kcal/mol suggesting no reactivity. On the contrary, taurolidine docking into E. coli fimbriae protein, responsible for bacteria adhesion to the bladder epithelium, shows it has higher affinity than mannose (the natural substrate, whereas methylol-taurultam and taurultam are less tightly bound. Since taurolidine is readily available because it is administered in high doses after peritonitis surgery, it may successfully compete with mannose explaining its effectiveness against bacterial infections at

  4. Expanding Interaction Potentials within Virtual Environments: Investigating the Usability of Speech and Manual Input Modes for Decoupled Interaction

    OpenAIRE

    Alex Stedmon; Victor Bayon; Gareth Griffiths

    2011-01-01

    Distributed technologies and ubiquitous computing now support users who may be detached or decoupled from traditional interactions. In order to investigate the potential usability of speech and manual input devices, an evaluation of speech input across different user groups and a usability assessment of independent-user and collaborative-user interactions was conducted. Whilst the primary focus was on a formative usability evaluation, the user group evaluation provided a formal basis to under...

  5. Effective potentials in concentrated colloid-polymer mixtures with competing interactions

    Science.gov (United States)

    Laurati, Marco; Valadez Perez, Nestor; Capellmann, Ronja; Egelhaaf, Stefan; Castañeda-Priego, Ramon

    We determine the effective potentials describing the interactions between colloidal particles in concentrated colloid-polymer mixtures in which depletion attraction competes with electrostatic repulsion. To obtain the potentials, the method of Monte-Carlo inversion is applied to experimental pair distribution functions obtained by confocal microscopy. Both fluid and gel states are investigated. We compare the results of the inversion method with those obtained by describing the interactions using a combination of a square well potential for the attractive component and a Yukawa potential for the repulsive component. This allows us to test the validity range of the one-component pair-potential.

  6. On the theory of interaction potentials in ionic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Acevedo, Roberto [Departamento de Ciencia de los Materiales, Facultad de Ciencias Fisicas y Matematicas, Beauchef 850, Santiago (Chile); Soto-Bubert, Andres [Instituto de Ciencias Basicas, Facultad de Ingenieria, Universidad Diego Portales, Avenida Ejercito 441, Santiago (Chile)], E-mail: roberto.acevedo@umayor.cl

    2008-11-01

    The aim of this research work is to report a more comprehensive and detailed study of both, the intermolecular and intramolecular potencial functions with reference to the various families of the elpasolite type crystals. The cohesive energy has been thought as a sum of three terms; the long range (Coulombic), the Born and the van der Waals contributions to the total energy. The Born-Mayer-Buckingham potential{sup 1} has been employed in all of these current studies and a number of convergence tests are analyzed from a formal viewpoint. Our work has been focused to the following systems: Cs{sub 2}NaLnF{sub 6}, Cs{sub 2}NaLnCl{sub 6}, Cs{sub 2}NaLnBr{sub 6}, Rb{sub 2}NaLnF{sub 6} and Cs{sub 2}KLnF{sub 6} in the Fm3m space group. A substantial amount of theoretical models have been analyzed and several computing simulations have been undertaken to estimate the reticular energies and the corresponding heat of formation for these crystals. To achieve this goal, a Born-Haber thermodynamic cycle has been introduced in our model. It is shown that the calculated energy values are reasonable and follow the expected trend along the lanthanide series in the periodic chart. We also discuss the advantages and disadvantages of the current and proposed generalized model. The most likely sources for improvement are discussed in detail. New convergence tests as well as some master equations have been introduced to study the various diagonal contributions to the total energy.

  7. Phase transition of strongly interacting matter with a chemical potential dependent Polyakov loop potential

    Science.gov (United States)

    Shao, Guo-yun; Tang, Zhan-duo; Di Toro, Massimo; Colonna, Maria; Gao, Xue-yan; Gao, Ning

    2016-07-01

    We construct a hadron-quark two-phase model based on the Walecka-quantum hadrodynamics and the improved Polyakov-Nambu-Jona-Lasinio (PNJL) model with an explicit chemical potential dependence of Polyakov loop potential (μ PNJL model). With respect to the original PNJL model, the confined-deconfined phase transition is largely affected at low temperature and large chemical potential. Using the two-phase model, we investigate the equilibrium transition between hadronic and quark matter at finite chemical potentials and temperatures. The numerical results show that the transition boundaries from nuclear to quark matter move towards smaller chemical potential (lower density) when the μ -dependent Polyakov loop potential is taken. In particular, for charge asymmetric matter, we compute the local asymmetry of u , d quarks in the hadron-quark coexisting phase, and analyze the isospin-relevant observables possibly measurable in heavy-ion collision (HIC) experiments. In general new HIC data on the location and properties of the mixed phase would bring relevant information on the expected chemical potential dependence of the Polyakov loop contribution.

  8. Identification of potential target levels for Central Baltic Sea fishing mortalities, taking multispecies interactions into account

    DEFF Research Database (Denmark)

    Vinther, Morten; Neuenfeldt, Stefan; Eero, Margit;

    2012-01-01

    The main biological interactions between Baltic cod, herring and sprat have been modelled in a stochastic multispecies (SMS) model. Based on this, a simple approach has been developed to quantify candidates for FMSY proxies (fishing mortality that produces the maximum sustainable yield) in a...

  9. Controlling Soliton Collisions of Condensates by Time-Dependence of Both Interactions and External Potential

    Institute of Scientific and Technical Information of China (English)

    何章明; 王登龙; 丁建文; 颜晓红

    2012-01-01

    Considering time-dependence of both interactions and external potential,we analytically study the collisional behaviors of two bright solitons in Bose-Einstein condensates by using Darboux transformation.It is found that for a closed external potential,the soliton-soliton distance is decreased with nonlinearly increased interactions,while the amplitude of each soliton increases and its width decreases.For linearly increased interactions but nonlinearly decreased external potential,especially,the atom transfer between two solitons is observed,different from previous theory of no atom transfer in solitons collision in a fixed external potential.In addition,it is shown that the collisional type,such as head-on,"chase",or collision period between two solitons,can be controlled by tuning both interactions and external potential.The predicted phenomena can be observed under the condition of the current experiments and open possibilities for future application in atoms transport.

  10. Interactions of physical, chemical, and biological weather calling for an integrated approach to assessment, forecasting, and communication of air quality.

    Science.gov (United States)

    Klein, Thomas; Kukkonen, Jaakko; Dahl, Aslög; Bossioli, Elissavet; Baklanov, Alexander; Vik, Aasmund Fahre; Agnew, Paul; Karatzas, Kostas D; Sofiev, Mikhail

    2012-12-01

    This article reviews interactions and health impacts of physical, chemical, and biological weather. Interactions and synergistic effects between the three types of weather call for integrated assessment, forecasting, and communication of air quality. Today's air quality legislation falls short of addressing air quality degradation by biological weather, despite increasing evidence for the feasibility of both mitigation and adaptation policy options. In comparison with the existing capabilities for physical and chemical weather, the monitoring of biological weather is lacking stable operational agreements and resources. Furthermore, integrated effects of physical, chemical, and biological weather suggest a critical review of air quality management practices. Additional research is required to improve the coupled modeling of physical, chemical, and biological weather as well as the assessment and communication of integrated air quality. Findings from several recent COST Actions underline the importance of an increased dialog between scientists from the fields of meteorology, air quality, aerobiology, health, and policy makers.

  11. Usefulness and limitations of dK random graph models to predict interactions and functional homogeneity in biological networks under a pseudo-likelihood parameter estimation approach

    Directory of Open Access Journals (Sweden)

    Luan Yihui

    2009-09-01

    Full Text Available Abstract Background Many aspects of biological functions can be modeled by biological networks, such as protein interaction networks, metabolic networks, and gene coexpression networks. Studying the statistical properties of these networks in turn allows us to infer biological function. Complex statistical network models can potentially more accurately describe the networks, but it is not clear whether such complex models are better suited to find biologically meaningful subnetworks. Results Recent studies have shown that the degree distribution of the nodes is not an adequate statistic in many molecular networks. We sought to extend this statistic with 2nd and 3rd order degree correlations and developed a pseudo-likelihood approach to estimate the parameters. The approach was used to analyze the MIPS and BIOGRID yeast protein interaction networks, and two yeast coexpression networks. We showed that 2nd order degree correlation information gave better predictions of gene interactions in both protein interaction and gene coexpression networks. However, in the biologically important task of predicting functionally homogeneous modules, degree correlation information performs marginally better in the case of the MIPS and BIOGRID protein interaction networks, but worse in the case of gene coexpression networks. Conclusion Our use of dK models showed that incorporation of degree correlations could increase predictive power in some contexts, albeit sometimes marginally, but, in all contexts, the use of third-order degree correlations decreased accuracy. However, it is possible that other parameter estimation methods, such as maximum likelihood, will show the usefulness of incorporating 2nd and 3rd degree correlations in predicting functionally homogeneous modules.

  12. Phase transition of strongly interacting matter with a chemical potential dependent Polyakov loop potential

    CERN Document Server

    Shao, Guo-yun; Di Toro, Massimo; Colonna, Maria; Gao, Xue-yan; Gao, Ning

    2016-01-01

    We construct a hadron-quark two-phase model based on the Walecka-quantum hadrodynamics and the improved Polyakov-Nambu--Jona-Lasinio model with an explicit chemical potential dependence of Polyakov-loop potential ($\\mu$PNJL model). With respect to the original PNJL model, the confined-deconfined phase transition is largely affected at low temperature and large chemical potential. Using the two-phase model, we investigate the equilibrium transition between hadronic and quark matter at finite chemical potentials and temperatures. The numerical results show that the transition boundaries from nuclear to quark matter move towards smaller chemical potential (lower density) when the $\\mu$-dependent Polyakov loop potential is taken. In particular, for charge asymmetric matter, we compute the local asymmetry of $u, d$ quarks in the hadron-quark coexisting phase, and analyse the isospin-relevant observables possibly measurable in heavy-ion collision (HIC) experiments. In general new HIC data on the location and proper...

  13. Numerical modelling of thermal effects on biological tissue during laser-material interaction

    Science.gov (United States)

    Latinovic, Z.; Sreckovic, M.; Janicijevic, M.; Ilic, J.; Radovanovic, J.

    2014-09-01

    Among numerous methods of the modelling of laser interaction with the material equivalent of biological tissue (including macroscopic and microscopic cell interaction), the case of pathogenic prostates is chosen to be studied. The principal difference between the inorganic and tissue equivalent material is the term which includes blood flow. Thermal modelling is chosen for interaction mechanisms, i.e. bio-heat equation. It was noticed that the principal problems are in selecting appropriate numerical methods, available mathematical program packages and finding all exact parameters for performing the needed calculations. As principal parameters, among them density, heat conduction, and specific heat, there are many other parameters which depend on the chosen approach (there could be up to 20 parameters, among them coefficient of time scaling, arterial blood temperature, metabolic heat source, etc). The laser type, including its wavelength which defines the quantity of absorbed energy and dynamic of irradiation, presents the term which could be modulated for the chosen problem. In this study, the program Comsol Multiphysics 3.5 is used in the simulation of prostate exposed to Nd3+:YAG laser in its fundamental mode.

  14. Numerical modelling of thermal effects on biological tissue during laser-material interaction

    International Nuclear Information System (INIS)

    Among numerous methods of the modelling of laser interaction with the material equivalent of biological tissue (including macroscopic and microscopic cell interaction), the case of pathogenic prostates is chosen to be studied. The principal difference between the inorganic and tissue equivalent material is the term which includes blood flow. Thermal modelling is chosen for interaction mechanisms, i.e. bio-heat equation. It was noticed that the principal problems are in selecting appropriate numerical methods, available mathematical program packages and finding all exact parameters for performing the needed calculations. As principal parameters, among them density, heat conduction, and specific heat, there are many other parameters which depend on the chosen approach (there could be up to 20 parameters, among them coefficient of time scaling, arterial blood temperature, metabolic heat source, etc). The laser type, including its wavelength which defines the quantity of absorbed energy and dynamic of irradiation, presents the term which could be modulated for the chosen problem. In this study, the program Comsol Multiphysics 3.5 is used in the simulation of prostate exposed to Nd3+:YAG laser in its fundamental mode. (paper)

  15. The potential use of SUISEKI as a protein interaction discovery tool.

    Science.gov (United States)

    Blaschke, C; Valencia, A

    2001-01-01

    Relevant information about protein interactions is stored in textual sources. This sources are commonly used not only as archives of what is already known but also as information for generating new knowledge, particularly to pose hypothesis about new possible interactions that can be inferred from the existing ones. This task is the more creative part of scientific work in experimental systems. We present a large-scale analysis for the prediction of new interactions based on the interaction network for the ones already known and detected automatically in the literature. During the last few years it has became clear that part of the information about protein interactions could be extracted with automatic tools, even if these tools are still far from perfect and key problems such as detection of protein names are not completely solved. We have developed a integrated automatic approach, called SUISEKI (System for Information Extraction on Interactions), able to extract protein interactions from collections of Medline abstracts. Previous experiments with the system have shown that it is able to extract almost 70% of the interactions present in relatively large text corpus, with an accuracy of approximately 80% (for the best defined interactions) that makes the system usable in real scenarios, both at the level of extraction of protein names and at the level of extracting interaction between them. With the analysis of the interaction map of Saccharomyces cerevisiae we show that interactions published in the years 2000/2001 frequently correspond to proteins or genes that were already very close in the interaction network deduced from the literature published before these years and that they are often connected to the same proteins. That is, discoveries are commonly done among highly connected entities. Some biologically relevant examples illustrate how interactions described in the year 2000 could have been proposed as reasonable working hypothesis with the information

  16. Profiling IgG N-glycans as potential biomarker of chronological and biological ages

    Science.gov (United States)

    Yu, Xinwei; Wang, Youxin; Kristic, Jasminka; Dong, Jing; Chu, Xi; Ge, Siqi; Wang, Hao; Fang, Honghong; Gao, Qing; Liu, Di; Zhao, Zhongyao; Peng, Hongli; Pucic Bakovic, Maja; Wu, Lijuan; Song, Manshu; Rudan, Igor; Campbell, Harry; Lauc, Gordan; Wang, Wei

    2016-01-01

    Abstract As an important post-translation modifying process, glycosylation significantly affects the structure and function of immunoglobulin G (IgG) molecules and is essential in many steps of the inflammatory cascade. Studies have demonstrated the potential of using glycosylation features of IgG as a component of predictive biomarkers for chronological age in several European populations, whereas no study has been reported in Chinese. Herein, we report various patterns of changes in IgG glycosylation associated with age by analyzing IgG glycosylation in 701 community-based Han Chinese (244 males, 457 females; 23–68 years old). Eleven IgG glycans, including FA2B, A2G1, FA2[6]G1, FA2[3]G1, FA2[6]BG1, FA2[3]BG1, A2G2, A2BG2, FA2G2, FA2G2S1, and FA2G2S2, change considerably with age and specific combinations of these glycan features can explain 23.3% to 45.4% of the variance in chronological age in this population. This indicates that these combinations of glycan features provide more predictive information than other single markers of biological age such as telomere length. In addition, the clinical traits such as fasting plasma glucose and aspartate aminotransferase associated with biological age are strongly correlated with the combined glycan features. We conclude that IgG glycosylation appears to correlate with both chronological and biological ages, and thus its possible role in the aging process merits further study. PMID:27428197

  17. Potential biological applications of bio-based anacardic acids and their derivatives.

    Science.gov (United States)

    Hamad, Fatma B; Mubofu, Egid B

    2015-01-01

    Cashew nut shells (CNS), which are agro wastes from cashew nut processing factories, have proven to be among the most versatile bio-based renewable materials in the search for functional materials and chemicals from renewable resources. CNS are produced in the cashew nut processing process as waste, but they contain cashew nut shell liquid (CNSL) up to about 30-35 wt. % of the nut shell weight depending on the method of extraction. CNSL is a mixture of anacardic acid, cardanol, cardol, and methyl cardol, and the structures of these phenols offer opportunities for the development of diverse products. For anacardic acid, the combination of phenolic, carboxylic, and a 15-carbon alkyl side chain functional group makes it attractive in biological applications or as a synthon for the synthesis of a multitude of bioactive compounds. Anacardic acid, which is about 65% of a CNSL mixture, can be extracted from the agro waste. This shows that CNS waste can be used to extract useful chemicals and thus provide alternative green sources of chemicals, apart from relying only on the otherwise declining petroleum based sources. This paper reviews the potential of anacardic acids and their semi-synthetic derivatives for antibacterial, antitumor, and antioxidant activities. The review focuses on natural anacardic acids from CNS and other plants and their semi-synthetic derivatives as possible lead compounds in medicine. In addition, the use of anacardic acid as a starting material for the synthesis of various biologically active compounds and complexes is reported. PMID:25894225

  18. Potential of chicken by-products as sources of useful biological resources

    International Nuclear Information System (INIS)

    By-products from different animal sources are currently being utilised for beneficial purposes. Chicken processing plants all over the world generate large amount of solid by-products in form of heads, legs, bones, viscera and feather. These wastes are often processed into livestock feed, fertilizers and pet foods or totally discarded. Inappropriate disposal of these wastes causes environmental pollution, diseases and loss of useful biological resources like protein, enzymes and lipids. Utilisation methods that make use of these biological components for producing value added products rather than the direct use of the actual waste material might be another viable option for dealing with these wastes. This line of thought has consequently led to researches on these wastes as sources of protein hydrolysates, enzymes and polyunsaturated fatty acids. Due to the multi-applications of protein hydrolysates in various branches of science and industry, and the large body of literature reporting the conversion of animal wastes to hydrolysates, a large section of this review was devoted to this subject. Thus, this review reports the known functional and bioactive properties of hydrolysates derived from chicken by-products as well their utilisation as source of peptone in microbiological media. Methods of producing these hydrolysates including their microbiological safety are discussed. Based on the few references available in the literature, the potential of some chicken by-product as sources of proteases and polyunsaturated fatty acids are pointed out along with some other future applications

  19. Potential Biological Applications of Bio-Based Anacardic Acids and Their Derivatives

    Directory of Open Access Journals (Sweden)

    Fatma B. Hamad

    2015-04-01

    Full Text Available Cashew nut shells (CNS, which are agro wastes from cashew nut processing factories, have proven to be among the most versatile bio-based renewable materials in the search for functional materials and chemicals from renewable resources. CNS are produced in the cashew nut processing process as waste, but they contain cashew nut shell liquid (CNSL up to about 30–35 wt. % of the nut shell weight depending on the method of extraction. CNSL is a mixture of anacardic acid, cardanol, cardol, and methyl cardol, and the structures of these phenols offer opportunities for the development of diverse products. For anacardic acid, the combination of phenolic, carboxylic, and a 15-carbon alkyl side chain functional group makes it attractive in biological applications or as a synthon for the synthesis of a multitude of bioactive compounds. Anacardic acid, which is about 65% of a CNSL mixture, can be extracted from the agro waste. This shows that CNS waste can be used to extract useful chemicals and thus provide alternative green sources of chemicals, apart from relying only on the otherwise declining petroleum based sources. This paper reviews the potential of anacardic acids and their semi-synthetic derivatives for antibacterial, antitumor, and antioxidant activities. The review focuses on natural anacardic acids from CNS and other plants and their semi-synthetic derivatives as possible lead compounds in medicine. In addition, the use of anacardic acid as a starting material for the synthesis of various biologically active compounds and complexes is reported.

  20. Dysfunctional Hematopoietic Stem Cell Biology: Underlying Mechanisms and Potential Therapeutic Strategies

    Directory of Open Access Journals (Sweden)

    Anja Geiselhart

    2012-01-01

    Full Text Available Fanconi anemia (FA is the most common inherited bone marrow failure syndrome. FA patients suffer to varying degrees from a heterogeneous range of developmental defects and, in addition, have an increased likelihood of developing cancer. Almost all FA patients develop a severe, progressive bone marrow failure syndrome, which impacts upon the production of all hematopoietic lineages and, hence, is thought to be driven by a defect at the level of the hematopoietic stem cell (HSC. This hypothesis would also correlate with the very high incidence of MDS and AML that is observed in FA patients. In this paper, we discuss the evidence that supports the role of dysfunctional HSC biology in driving the etiology of the disease. Furthermore, we consider the different model systems currently available to study the biology of cells defective in the FA signaling pathway and how they are informative in terms of identifying the physiologic mediators of HSC depletion and dissecting their putative mechanism of action. Finally, we ask whether the insights gained using such disease models can be translated into potential novel therapeutic strategies for the treatment of the hematologic disorders in FA patients.

  1. Potential of chicken by-products as sources of useful biological resources

    Energy Technology Data Exchange (ETDEWEB)

    Lasekan, Adeseye [Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Abu Bakar, Fatimah, E-mail: fatim@putra.upm.edu.my [Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Halal Products Research Institute, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Hashim, Dzulkifly [Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Halal Products Research Institute, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia)

    2013-03-15

    By-products from different animal sources are currently being utilised for beneficial purposes. Chicken processing plants all over the world generate large amount of solid by-products in form of heads, legs, bones, viscera and feather. These wastes are often processed into livestock feed, fertilizers and pet foods or totally discarded. Inappropriate disposal of these wastes causes environmental pollution, diseases and loss of useful biological resources like protein, enzymes and lipids. Utilisation methods that make use of these biological components for producing value added products rather than the direct use of the actual waste material might be another viable option for dealing with these wastes. This line of thought has consequently led to researches on these wastes as sources of protein hydrolysates, enzymes and polyunsaturated fatty acids. Due to the multi-applications of protein hydrolysates in various branches of science and industry, and the large body of literature reporting the conversion of animal wastes to hydrolysates, a large section of this review was devoted to this subject. Thus, this review reports the known functional and bioactive properties of hydrolysates derived from chicken by-products as well their utilisation as source of peptone in microbiological media. Methods of producing these hydrolysates including their microbiological safety are discussed. Based on the few references available in the literature, the potential of some chicken by-product as sources of proteases and polyunsaturated fatty acids are pointed out along with some other future applications.

  2. Radiation-induced apoptosis in human lymphocytes: Potential as a biological dosimeter

    International Nuclear Information System (INIS)

    We have tested the possibility of using apoptosis (programmed cell death) in human peripheral blood lymphocytes as a short-term biological dosimeter. Lymphocytes isolated from whole blood were irradiated in culture with 250 kVp x-rays or 60Co gamma rays. Two assays were used to measure apoptosis in lymphocytes after irradiation: in situ terminal deoxynucleotidyl transferase assay and fluorescence analysis of DNA unwinding assay. Similar qualitative and quantitative results were produced by the assays, supporting the notion that the fluorescence analysis of DNA unwinding assay measured DNA fragmentation associated with apoptosis. Induction of apoptosis in lymphocytes irradiated in vitro was proportional to dose and could be detected following exposures as low as 0.05 Gy. Lymphocytes irradiated in vitro was proportional to dose and could be detected following exposures as low as 0.05 Gy. Lymphocytes from individual donors had reproducible dose responses. There was, however, variation between donors. X-ray and gamma-ray exposures induced similar levels of apoptosis at similar doses. The induction kinetics of apoptosis in vitro indicate a maximum is reached about 72 h after irradiation. In conclusion, the in vitro experimental evidence indicates that radiation-induced apoptosis in human lymphocytes has the kinetics, sensitivity, and reproductibility to be a potential biological dosimeter. 29 refs., 5 figs

  3. The biology of cancer testis antigens: putative function, regulation and therapeutic potential.

    Science.gov (United States)

    Fratta, Elisabetta; Coral, Sandra; Covre, Alessia; Parisi, Giulia; Colizzi, Francesca; Danielli, Riccardo; Nicolay, Hugues Jean Marie; Sigalotti, Luca; Maio, Michele

    2011-04-01

    Cancer testis antigens (CTA) are a large family of tumor-associated antigens expressed in human tumors of different histological origin, but not in normal tissues except for testis and placenta. This tumor-restricted pattern of expression, together with their strong in vivo immunogenicity, identified CTA as ideal targets for tumor-specific immunotherapeutic approaches, and prompted the development of several clinical trials of CTA-based vaccine therapy. Driven by this practical clinical interest, a more detailed characterization of CTA biology has been recently undertaken. So far, at least 70 families of CTA, globally accounting for about 140 members, have been identified. Most of these CTA are expressed during spermatogenesis, but their function is still largely unknown. Epigenetic events, particularly DNA methylation, appear to be the primary mechanism regulating CTA expression in both normal and transformed cells, as well as in cancer stem cells. In view of the growing interest in CTA biology, the aim of this review is to provide the most recent information on their expression, regulation and function, together with a brief summary of the major clinical trials involving CTA as therapeutic agents. The pharmacologic modulation of CTA expression profiles on neoplastic cells by DNA hypomethylating drugs will also be discussed as a feasible approach to design new combination therapies potentially able to improve the clinical efficacy of currently adopted CTA-based immunotherapeutic regimens in cancer patients.

  4. Biological dosimetry: the potential use of radiation-induced apoptosis in human T-lymphocytes

    International Nuclear Information System (INIS)

    An assay for biological dosimetry based on the induction of apoptosis in human T-lymphocytes is described. Radiation-induced apoptosis was assessed by flow cytometric identification of cells displaying apoptosis-associated DNA condensation. CD4 and CD8 T-lymphocytes were analysed. They were recognized on the basis of their cell-surface antigens. Four parameters were measured for both cell types: cell size, granularity, antigen immunofluorescence and DNA content. Apoptosis was quantified as the fraction of CD4-, or CD8-positive cells with a characteristic reduction of cell size and DNA content. At doses below 1 Gy, levels of radiation-induced apoptosis increased for up to 5 days after irradiation. Optimal dose discrimination was observed 4 days after irradiation, at which time the dose-response curves were linear, with a slope of 8% ± 0.5% per 0.1 Gy. In controlled, dose-response experiments the lowest dose level at which the radiation-induced apoptosis frequency was still significantly above control was 0.05 Gy. After 5 days post-irradiation incubation, intra- and interdonor variations were measured and found to be similar; thus, apoptotic levels depend more on the dose than on the donor. The results demonstrate the potential of this assay as a biological dosimeter. (orig.)

  5. BROMOC suite: Monte Carlo/Brownian dynamics suite for studies of ion permeation and DNA transport in biological and artificial pores with effective potentials.

    Science.gov (United States)

    De Biase, Pablo M; Markosyan, Suren; Noskov, Sergei

    2015-02-01

    The transport of ions and solutes by biological pores is central for cellular processes and has a variety of applications in modern biotechnology. The time scale involved in the polymer transport across a nanopore is beyond the accessibility of conventional MD simulations. Moreover, experimental studies lack sufficient resolution to provide details on the molecular underpinning of the transport mechanisms. BROMOC, the code presented herein, performs Brownian dynamics simulations, both serial and parallel, up to several milliseconds long. BROMOC can be used to model large biological systems. IMC-MACRO software allows for the development of effective potentials for solute-ion interactions based on radial distribution function from all-atom MD. BROMOC Suite also provides a versatile set of tools to do a wide variety of preprocessing and postsimulation analysis. We illustrate a potential application with ion and ssDNA transport in MspA nanopore. PMID:25503688

  6. Student Interactions with CD-ROM Storybooks: A Look at Potential Relationships between Multiple Intelligence Strengths and Levels of Interaction

    Science.gov (United States)

    Huffman, Celia A.

    2012-01-01

    This study looked at the potential relationship that may exist between students' intelligence strengths, in particular their spatial and kinesthetic strengths, and their combined cognitive and metacognitive levels of interaction with a CD-ROM storybook. The multiple intelligence strengths of a sample of students, measured via the MIDAS/My…

  7. Velocity dependence of angular distributions in gas/solid--surface collisions: Relationship to the interaction potential

    Energy Technology Data Exchange (ETDEWEB)

    Brady, J.W. Jr.; Doll, J.D.; Thompson, D.L.

    1978-10-15

    The angular and velocity distributions for gas/solid-surface collisions are examined. It is shown that the envelope of the scattered phase-space distribution is quite sensitive to the gas/surface interaction potential.

  8. Stability of stationary states of non-local equations with singular interaction potentials

    KAUST Repository

    Fellner, Klemens

    2011-04-01

    We study the large-time behaviour of a non-local evolution equation for the density of particles or individuals subject to an external and an interaction potential. In particular, we consider interaction potentials which are singular in the sense that their first derivative is discontinuous at the origin.For locally attractive singular interaction potentials we prove under a linear stability condition local non-linear stability of stationary states consisting of a finite sum of Dirac masses. For singular repulsive interaction potentials we show the stability of stationary states of uniformly bounded solutions under a convexity condition.Finally, we present numerical simulations to illustrate our results. © 2010 Elsevier Ltd.

  9. Stochastic description of the ligand-receptor interaction of biologically active substances at extremely low doses.

    Science.gov (United States)

    Gurevich, Konstantin G; Agutter, Paul S; Wheatley, Denys N

    2003-04-01

    Signalling molecules can be effective at extraordinarily low concentrations (down to attomolar levels). To handle such cases, probabilistic methods have been used to describe the formal kinetics of action of biologically active substances in these low doses, although it has been necessary to review what is meant by such a term. The mean numbers of transformed/degraded molecules and their dispersions were calculated for the possible range of ligand-receptor binding schemes. We used both analytical equations and numerical simulations to calculate the coefficients of variation (ratio of standard deviation to mean) and demonstrated that the distribution of the coefficient is highly dependent on the reaction scheme. It may, therefore, be used as an additional factor for discriminating between cooperative and noncooperative models of ligand-receptor interaction over extreme ranges of ligand dilution. The relevance to signalling behaviour is discussed.

  10. Neutron interactions with biological tissue. Progress report, December 1, 1993--November 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    An attempt is made to obtain information about the physical stage of neutron interactions with tissue through secondary charged particles. The authors use theoretical calculations whose input includes neutron cross section data; range, stopping power, ion yield, and straggling information; and geometrical properties. Outputs are initial and slowing-down spectra of charged particles, kerma factors, average values of quality factors, microdosimetric spectra, and integral microdosimetric parameters such as {bar y}{sub F}, {bar y}{sub D}, y{sup *}. Since it has become apparent that nanometer site sizes are more relevant to radiobiological effects, the calculations of event size spectra and their parameters have been extended to these smaller diameters. This information is basic to radiological physics, radiation biology, radiation protection of workers, and standards for neutron dose measurement.

  11. Mechanisms of interaction and biological effects of extremely-low-frequency electromagnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Tenforde, T.S.

    1994-07-01

    Evidence is mounting, that environmental electric and magnetic fields in the extremely-low-frequency (ELF) band below 300 Hz can influence biological functions by mechanisms that are only poorly understood at the present time. The primary objectives of this paper are to review the physical properties of ELF fields, their interactions with living systems at the tissue, cellular, and subcellular levels, and the key role of cell membranes in the transduction of signals from imposed ELF fields. Topics of discussion include signal-to-noise ratios for single cells and cell aggregates, resonance phenomena involving a combination of static and ELF magnetic fields, and the possible influence of ELF fields on molecular signaling pathways that involve membrane receptors and cytoplasmic second messengers. The implications of these findings for promotion of tumor growth by ELF fields are also reviewed.

  12. Conjugation of cholesterol to HIV-1 fusion inhibitor C34 increases peptide-membrane interactions potentiating its action.

    Directory of Open Access Journals (Sweden)

    Axel Hollmann

    Full Text Available Recently, the covalent binding of a cholesterol moiety to a classical HIV-1 fusion inhibitor peptide, C34, was shown to potentiate its antiviral activity. Our purpose was to evaluate the interaction of cholesterol-conjugated and native C34 with membrane model systems and human blood cells to understand the effects of this derivatization. Lipid vesicles and monolayers with defined compositions were used as model membranes. C34-cholesterol partitions more to fluid phase membranes that mimic biological membranes. Importantly, there is a preference of the conjugate for liquid ordered membranes, rich in cholesterol and/or sphingomyelin, as observed both from partition and surface pressure studies. In human erythrocytes and peripheral blood mononuclear cells (PBMC, C34-cholesterol significantly decreases the membrane dipole potential. In PBMC, the conjugate was 14- and 115-fold more membranotropic than T-1249 and enfuvirtide, respectively. C34 or cholesterol alone did not show significant membrane activity. The enhanced interaction of C34-cholesterol with biological membranes correlates with its higher antiviral potency. Higher partitions for lipid-raft like compositions direct the drug to the receptor-rich domains where membrane fusion is likely to occur. This intermediary membrane binding step may facilitate the drug delivery to gp41 in its pre-fusion state.

  13. A review on computational systems biology of pathogen-host interactions.

    Science.gov (United States)

    Durmuş, Saliha; Çakır, Tunahan; Özgür, Arzucan; Guthke, Reinhard

    2015-01-01

    Pathogens manipulate the cellular mechanisms of host organisms via pathogen-host interactions (PHIs) in order to take advantage of the capabilities of host cells, leading to infections. The crucial role of these interspecies molecular interactions in initiating and sustaining infections necessitates a thorough understanding of the corresponding mechanisms. Unlike the traditional approach of considering the host or pathogen separately, a systems-level approach, considering the PHI system as a whole is indispensable to elucidate the mechanisms of infection. Following the technological advances in the post-genomic era, PHI data have been produced in large-scale within the last decade. Systems biology-based methods for the inference and analysis of PHI regulatory, metabolic, and protein-protein networks to shed light on infection mechanisms are gaining increasing demand thanks to the availability of omics data. The knowledge derived from the PHIs may largely contribute to the identification of new and more efficient therapeutics to prevent or cure infections. There are recent efforts for the detailed documentation of these experimentally verified PHI data through Web-based databases. Despite these advances in data archiving, there are still large amounts of PHI data in the biomedical literature yet to be discovered, and novel text mining methods are in development to unearth such hidden data. Here, we review a collection of recent studies on computational systems biology of PHIs with a special focus on the methods for the inference and analysis of PHI networks, covering also the Web-based databases and text-mining efforts to unravel the data hidden in the literature.

  14. Development of Biological Movement Recognition by Interaction between Active Basis Model and Fuzzy Optical Flow Division

    Directory of Open Access Journals (Sweden)

    Bardia Yousefi

    2014-01-01

    Full Text Available Following the study on computational neuroscience through functional magnetic resonance imaging claimed that human action recognition in the brain of mammalian pursues two separated streams, that is, dorsal and ventral streams. It follows up by two pathways in the bioinspired model, which are specialized for motion and form information analysis (Giese and Poggio 2003. Active basis model is used to form information which is different from orientations and scales of Gabor wavelets to form a dictionary regarding object recognition (human. Also biologically movement optic-flow patterns utilized. As motion information guides share sketch algorithm in form pathway for adjustment plus it helps to prevent wrong recognition. A synergetic neural network is utilized to generate prototype templates, representing general characteristic form of every class. Having predefined templates, classifying performs based on multitemplate matching. As every human action has one action prototype, there are some overlapping and consistency among these templates. Using fuzzy optical flow division scoring can prevent motivation for misrecognition. We successfully apply proposed model on the human action video obtained from KTH human action database. Proposed approach follows the interaction between dorsal and ventral processing streams in the original model of the biological movement recognition. The attained results indicate promising outcome and improvement in robustness using proposed approach.

  15. Systems biology-guided identification of synthetic lethal gene pairs and its potential use to discover antibiotic combinations

    DEFF Research Database (Denmark)

    Aziz, Ramy K.; Monk, Jonathan M.; Lewis, R. M.;

    2015-01-01

    and phenotype, but their ability to accurately simulate gene-gene interactions has not been investigated extensively. Here we assess how accurately a metabolic model for Escherichia coli computes one particular type of gene-gene interaction, synthetic lethality, and find that the accuracy rate is between 25......% and 43%. The most common failure modes were incorrect computation of single gene essentiality and biological information that was missing from the model. Moreover, we performed virtual and biological screening against several synthetic lethal pairs to explore whether two-compound formulations could...

  16. Potential drug interactions : exposure and management in hospital and ambulatory settings

    OpenAIRE

    Indermitte, Jörg Lorenz

    2006-01-01

    Health care professionals are responsible to ensure safe dispensing and use of drug regimens involving the use of drug combinations that may interact and cause serious adverse events. In the last 40 years an enormous amount of data on drug interactions has been published. But, although potential drug interactions are probably common only few of them manifest serious adverse events and often only in predisposed patients. Therefore, health care professionals feel inundated with h...

  17. Nuclear Physics without High-Momentum Potentials: Direct Construction of the Effective Interaction from Scattering Observables

    CERN Document Server

    McElvain, Kenneth S

    2016-01-01

    The standard approach to nuclear physics encodes phase shift information in an NN potential, then decodes that information in forming an effective interaction, appropriate to a low-momentum Hilbert space. Here we show that it is instead possible to construct the effective interaction directly from continuum phase shifts and mixing angles, eliminating all reference to a high momentum potential. The theory is rapidly convergent and well behaved, yielding sub-keV accuracy.

  18. Peculiar features of the interaction potential between hydrogen and antihydrogen at intermediate separations

    Institute of Scientific and Technical Information of China (English)

    Lee Teck-Ghee; Wong Cheuk-Yin; Wang Lee-Shien

    2008-01-01

    This paper evaluates the interaction potential between a hydrogen and an antihydrogen using the second-order perturbation theory within the framework of the four-body system in a separable two-body basis. It finds that the H-H interaction potential possesses the peculiar features of a shallow local minimum located around interatomic separations of r ~ 6a.u. and a barrier rising at r<~ 5a.u.

  19. Biological Evaluation and Docking Analysis of Daturaolone as Potential Cyclooxygenase Inhibitor

    Directory of Open Access Journals (Sweden)

    Abdur Rauf

    2016-01-01

    Full Text Available This study deals with the isolation of the active constituent(s from a methanolic extract of Pistacia integerrima J. L. Stewart barks and it was also oriented to evaluate the in vivo and in silico anti-inflammatory activity. By NMR and crystallography techniques, we have isolated a triterpenoid identified as daturaolone (compound 1. This compound showed in vivo a significant and dose dependent (1–30 mg/kg anti-inflammatory activity on carrageenan-induced mouse paw oedema (ED50 = 10.1 mg/kg and on acetic acid-induced writhing responses in mice (ED50 = 13.8 mg/kg. In the in vivo experiments, the effect of tested compound was also evaluated in presence of the reference drug diclofenac (1–30 mg/kg. Moreover, in silico analysis of receptor ligand complex shows that compound 1 interacts with cyclooxygenases (COXs binding sites displaying an interesting interaction with COX-1. These findings suggest that compound 1 isolated from P. integerrima possesses in vivo anti-inflammatory and antinociceptive potentials, which are supported in silico by an interaction with COXs receptors.

  20. Selection of potential biological control of Exserohilum turcicum with epiphytic microorganisms from maize.

    Science.gov (United States)

    Sartori, Melina; Nesci, Andrea; Formento, Ángela; Etcheverry, Miriam

    2015-01-01

    The aims of this study were to select microbial isolates from phyllosphere of maize and to examine their antagonistic activity against Exserohilum turcicum. Selection was performed through the ability of isolates to compete with the pathogen using an index of dominance and to affect growth parameters of E. turcicum. Most of the epiphytic populations obtained for the screening were bacteria. These isolates were found in the order of 6 log CFU/g of leaf fresh weight. According to similar morphological characteristics and staining, 44 out of 111 isolates obtained were selected for testing antagonistic effects. At water potential, ψ, -1.38MPa and -4.19MPa, three Bacillus isolates showed dominance at a distance (5/0) and a significant reduction of growth rate of the pathogen. Three Bacillus isolates only decreased the growth rate of E. turcicum at -1.38MPa. At -4.19MPa the growth rate decreased with three isolates of Pantoea and three Bacillus. In this study a negative and significant correlation was observed between the growth rate of E. turcicum and the dominance index in the interaction of the pathogen with some bacteria. These results show that with decreasing growth rate of the pathogen the dominance index of the interaction increases. Eleven potential biocontrol agents against E. turcicum were selected. PMID:25771226

  1. Reactive Boundary Conditions as Limits of Interaction Potentials for Brownian and Langevin Dynamics

    CERN Document Server

    Chapman, S Jonathan; Isaacson, Samuel A

    2015-01-01

    A popular approach to modeling bimolecular reactions between diffusing molecules is through the use of reactive boundary conditions. One common model is the Smoluchowski partial absorption condition, which uses a Robin boundary condition in the separation coordinate between two possible reactants. This boundary condition can be interpreted as an idealization of a reactive interaction potential model, in which a potential barrier must be surmounted before reactions can occur. In this work we show how the reactive boundary condition arises as the limit of an interaction potential encoding a steep barrier within a shrinking region in the particle separation, where molecules react instantly upon reaching the peak of the barrier. The limiting boundary condition is derived by the method of matched asymptotic expansions, and shown to depend critically on the relative rate of increase of the barrier height as the width of the potential is decreased. Limiting boundary conditions for the same interaction potential in b...

  2. Potential of Root Exudates from Wetland Plants and Their Potential Role for Denitrification and Allelopathic Interactions

    DEFF Research Database (Denmark)

    Zhai, Xu

    Root exudates from wetland plants have both positive and negative interactions among microbe, plants and ecosystems. Wetland species releasing organic carbon into the rhizosphere for providing energy to denitrifying bacteria fuel denitrification for removal nitrogen in subsurface flow constructed...... wetlands. Furthermore, environmental factors such as temperature and light-regime affect the photosynthetic carbon fixation, which continuously influence the compositions and quantity of root exudates released into rhizosphere. Conversely, root exudates from invasive species might contain some phytotoxic...... chemicals to suppress the growth of native species. Phragmites australis is recognized as the most invasive species in wetland ecosystems in North America, and allelopathy has been reported to be involved in the invasion success of the introduced exotic P. australis. The composition of the root exudates may...

  3. Expanding Interaction Potentials within Virtual Environments: Investigating the Usability of Speech and Manual Input Modes for Decoupled Interaction

    Directory of Open Access Journals (Sweden)

    Alex Stedmon

    2011-01-01

    Full Text Available Distributed technologies and ubiquitous computing now support users who may be detached or decoupled from traditional interactions. In order to investigate the potential usability of speech and manual input devices, an evaluation of speech input across different user groups and a usability assessment of independent-user and collaborative-user interactions was conducted. Whilst the primary focus was on a formative usability evaluation, the user group evaluation provided a formal basis to underpin the academic rigor of the exercise. The results illustrate that using a speech interface is important in understanding user acceptance of such technologies. From the usability assessment it was possible to translate interactions and make them compatible with innovative input devices. This approach to interaction is still at an early stage of development, and the potential or validity of this interfacing concept is still under evaluation; however, as a concept demonstrator, the results of these initial evaluations demonstrate the potential usability issues of both input devices as well as highlighting their suitability for advanced virtual applications.

  4. Urgent Biophilia: Human-Nature Interactions and Biological Attractions in Disaster Resilience

    Directory of Open Access Journals (Sweden)

    Keith G. Tidball

    2012-06-01

    Full Text Available This contribution builds upon contemporary work on principles of biological attraction as well as earlier work on biophilia while synthesizing literatures on restorative environments, community-based ecological restoration, and both community and social-ecological disaster resilience. It suggests that when humans, faced with a disaster, as individuals and as communities and populations, seek engagement with nature to further their efforts to summon and demonstrate resilience in the face of a crisis, they exemplify an urgent biophilia. This urgent biophilia represents an important set of human-nature interactions in SES characterized by hazard, disaster, or vulnerability, often appearing in the 'backloop' of the adaptive cycle. The relationships that human-nature interactions have to other components within interdependent systems at many different scales may be one critical source of resilience in disaster and related contexts. In other words, the affinity we humans have for the rest of nature, the process of remembering that attraction, and the urge to express it through creation of restorative environments, which may also restore or increase ecological function, may confer resilience across multiple scales. In making this argument, the paper also represents a novel contribution to further theorizing alternatives to anthropocentric understandings of human-nature relations, and strongly makes the case for humans as part of, not separate from, ecosystems.

  5. Interaction of chemical species with biological regulation of the metabolism of essential trace elements

    Energy Technology Data Exchange (ETDEWEB)

    Windisch, W. [Center of Life and Food Sciences, Technische Univ. Muenchen, Freising (Germany)

    2002-02-01

    Variations in the chemical speciation of dietary trace elements can result in the provision of different amounts of these micronutrients to the organism and might thus induce interactions with trace-element metabolism. The chemical species of Zn, Fe, Cu, and Mn can interact with other components of the diet even before reaching the site of absorption, e.g. by formation of poorly soluble complexes with phytic acid. This might considerably modify the amount of metabolically available trace elements; differences between absorptive capacity per se toward dietary species seems to be less important. Homeostasis usually limits the quantities of Zn, Fe, Cu, and Mn transported from the gut into the organism, and differences between dietary species are largely eliminated at this step. There is no homeostatic control of absorption of Se and I, and organisms seem to be passively exposed to influx of these micronutrients irrespective of dietary speciation. Inside the organism the trace elements are usually converted into a metabolically recognizable form, channeled into their biological functions, or submitted to homeostatically controlled excretion. Some dietary species can, however, be absorbed as intact compounds. As long as the respective quantities of trace elements are not released from their carriers, they are not recognized properly by trace element metabolism and might induce tissue accumulation, irrespective of homeostatic control. (orig.)

  6. Towards the Biological Understanding of CTC: Capture Technologies, Definitions and Potential to Create Metastasis

    Directory of Open Access Journals (Sweden)

    Ana M.C. Barradas

    2013-12-01

    Full Text Available Circulating Tumor Cells (CTC are rare cells originated from tumors that travel into the blood stream, extravasate to different organs of which only a small fraction will develop into metastasis. The presence of CTC enumerated with the CellSearch system is associated with a relative short survival and their continued presence after the first cycles of therapy indicates a futile therapy in patients with metastatic carcinomas. Detailed characterization of CTC holds the promise to enable the choice of the optimal therapy for the individual patients during the course of the disease. The phenotype, physical and biological properties are however not well understood making it difficult to assess the merit of recent technological advancements to improve upon the capture of CTC or to evaluate their metastatic potential. Here we will discuss the recent advances in the classification of CTC captured by the CellSearch system, the implications of their features and numbers. Latest capture platforms are reviewed and placed in the light of technology improvements needed to detect CTC. Physical properties, phenotype, viability and proliferative potential and means to assess their proliferation and metastatic capacity will be summarized and placed in the context of the latest CTC capture platforms.

  7. Potential of chitinolytic Serratia marcescens strain JPP1 for biological control of Aspergillus parasiticus and aflatoxin.

    Science.gov (United States)

    Wang, Kai; Yan, Pei-Sheng; Cao, Li-Xin; Ding, Qing-Long; Shao, Chi; Zhao, Teng-Fei

    2013-01-01

    Serratia marcescens strain JPP1 was isolated from peanut hulls in Huai'an city, Jiangsu Province, China. Its potential to inhibit the mycelial growth of Aspergillus parasiticus and the subsequent aflatoxin production was evaluated. The strain JPP1 could produce chitinase to degrade fungal cell walls, which was the main mechanism of strain JPP1 for biocontrol. Scanning electron microscopy of fungi treated with the crude chitinase revealed abnormal morphological changes. While the strain was grown in the peanut hulls-based medium, the chitinase activity reached 7.39 units. RT-PCR analysis showed that the crude chitinase repressed the transcription of genes involved in the aflatoxin gene cluster, such as aflR, aflC (pksL1), and aflO (dmtA) genes. By visual agar plate assay and tip culture method, the strain JPP1 exhibited remarkable inhibitory effect on mycelia growth (antifungal ratio >95%) and subsequent aflatoxin production (antiaflatoxigenic ratio >98%). An in vitro assay with seed coating agent of bacterial suspension showed that strain JPP1 effectively reduced fungal growth and subsequent aflatoxin production on peanut seeds, and its antagonistic effect was superior to the common agricultural fungicide of carbendazim. These characteristics suggest that S. marcescens JPP1 strain could potentially be utilized for the biological control of phytopathogenic fungi and aflatoxin in Chinese peanut main producing areas.

  8. Potential nontarget effects of Metarhizium anisopliae (Deuteromycetes) used for biological control of ticks (Acari: Ixodidae)

    Science.gov (United States)

    Ginsberg, H.S.; LeBrun, R.A.; Heyer, K.; Zhioua, E.

    2002-01-01

    The potential for nontarget effects of the entomopathogenic fungus Metarhizium anisopliae (Metschnikoff) Sorokin, when used for biological control of ticks, was assessed in laboratory trials. Fungal pathogenicity was studied against convergent ladybird beetles, Hippodamia convergens Guerin-Meneville, house crickets, Acheta domesticus (L.), and milkweed bugs, Oncopeltus fasciatus (Dallas). Fungal spores applied with a spray tower produced significant mortality in H. convergens and A. domesticus, but effects on O. fasciatus were marginal. Treated insects placed with untreated individuals resulted in mortality from horizontal transmission to untreated beetles and crickets, but not milkweed bugs. Spread of fungal infection in the beetles resulted in mortality on days 4-10 after treatment, while in crickets mortality was on day 2 after treatment, suggesting different levels of pathogenicity and possibly different modes of transmission. Therefore, M. anisopliae varies in pathogenicity to different insects. Inundative applications can potentially affect nontarget species, but M. anisopliae is already widely distributed in North America, so applications for tick control generally would not introduce a novel pathogen into the environment. Pathogenicity in lab trials does not, by itself, demonstrate activity under natural conditions, so field trials are needed to confirm these results and to assess methods to minimize nontarget exposure.

  9. The Potential Use of Indigobush (Amorpha fruticosa L. as Natural Resource of Biologically Active Compounds

    Directory of Open Access Journals (Sweden)

    Tamara Jakovljević

    2015-05-01

    Full Text Available Background and Purpose: Recent research indicates that a weed like Indigobush (Amorpha fruticosa L. gives great opportunities for its commercialization through a rich spectrum of its beneficial biological features with possible use in the forestry and biotechnology field. Therefore, in this study we wanted to explore some of potential application of Indigobush extract, as a source of biologically active compounds, for animal cell culturing as well as green corrosion inhibitors. Materials and Methods: The effect of ethanol extract of Indigobush seeds was studied on human tumor cell lines (HeLa and MCF-7 and cell viability was determined by WST-1 method after 72 hours of treatment with 6 different extract concentrations (0.5-10 mg∙mL-1. The inhibition effect of Indigobush seeds extract on the corrosion of aluminum in 0.5 M hydrochloric acid solution was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS methods. Results: Results showed that the addition of Indigobush extract had a stimulatory effect on MCF-7 cells growth at the concentrations >1 mg∙mL-1 while the same effect on HeLa cells was observed only at the highest concentration of Indigobush extract (10 mg∙mL-1. The stimulatory effect of Indigobush extract on cell viability was more pronounced when the cells were grown in a medium with 5% FBS compared to 10% FBS (v/v. Indigobush extract did not show cytotoxic effect on MCF-7 and HeLa cells. Electrochemical studies showed that with increasing extract concentrations (2.5-15 mg∙mL-1 the values of corrosion current densities decrease, while the polarization resistance values increase. The maximum inhibition efficiency of Indigobush extract is reached at concentration of 15 mg∙mL-1 (82.9%. Conclusions: The Indigobush ethanol extract has no cytotoxic effect on human tumor cell lines MCF-7 and HeLa. Results confirmed that extract originated from Indigobush has the potential to utilize for the

  10. Palladium polypyridyl complexes: synthesis, characterization, DNA interaction and biological activity on Leishmania (L.) mexicana

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, Maribel [Instituto Venezolano de Investigaciones Cientificas, Caracas (Venezuela). Centro de Quimica; Betancourt, Adelmo [Universidad de Carabobo, Valencia (Venezuela). Facultad Experimental de Ciencia y Tecnologia. Dept. de Quimica; Hernandez, Clara [Universidad de Carabobo Sede Aragua, Maracay (Venezuela). Facultad de Ciencias de la Salud. Dept. de Ciencias Basicas; Marchan, Edgar [Universidad de Oriente, Cumana (Venezuela). Inst. de Investigaciones en Biomedicina y Ciencias Aplicadas. Nucleo de Sucre

    2008-07-01

    This paper describes the search for new potential chemotherapeutic agents based on transition metal complexes with planar ligands. In this study, palladium polypyridyl complexes were synthesized and characterized by elemental analysis, NMR, UV-VIS and IR spectroscopies. The interaction of the complexes with DNA was also investigated by spectroscopic methods. All metal-to-ligand charge transfer (MLCT) bands of the palladium polypyridyl complexes exhibited hypochromism and red shift in the presence of DNA. The binding constant and viscosity data suggested that the complexes [PdCl{sub 2}(phen)] and [PdCl{sub 2}(phendiamine)] interact with DNA by electrostatic forces. Additionally, these complexes induced an important leishmanistatic effect on L. (L.) mexicana promastigotes at the final concentration of 10 {mu}mol L{sup -1} in 48 h. (author)

  11. Warfarin and acetaminophen interaction: a summary of the evidence and biologic plausibility.

    Science.gov (United States)

    Lopes, Renato D; Horowitz, John D; Garcia, David A; Crowther, Mark A; Hylek, Elaine M

    2011-12-01

    Ms TS is a 66-year-old woman who receives warfarin for prevention of systemic embolization in the setting of hypertension, diabetes, and atrial fibrillation. She had a transient ischemic attack about 4 years ago when she was receiving aspirin. Her INR control was excellent; however, over the past few months it has become erratic, and her average dose required to maintain an INR of 2.0 to 3.0 appears to have decreased. She has had back pain over this same period and has been taking acetaminophen at doses at large as 650 mg four times daily, with her dose varying based on her symptoms. You recall a potential interaction and wonder if (1) her acetaminophen use is contributing to her loss of INR control, and (2) does this interaction place her at increased risk of warfarin-related complications? PMID:21911832

  12. Novel recurrent neural network for modelling biological networks: oscillatory p53 interaction dynamics.

    Science.gov (United States)

    Ling, Hong; Samarasinghe, Sandhya; Kulasiri, Don

    2013-12-01

    Understanding the control of cellular networks consisting of gene and protein interactions and their emergent properties is a central activity of Systems Biology research. For this, continuous, discrete, hybrid, and stochastic methods have been proposed. Currently, the most common approach to modelling accurate temporal dynamics of networks is ordinary differential equations (ODE). However, critical limitations of ODE models are difficulty in kinetic parameter estimation and numerical solution of a large number of equations, making them more suited to smaller systems. In this article, we introduce a novel recurrent artificial neural network (RNN) that addresses above limitations and produces a continuous model that easily estimates parameters from data, can handle a large number of molecular interactions and quantifies temporal dynamics and emergent systems properties. This RNN is based on a system of ODEs representing molecular interactions in a signalling network. Each neuron represents concentration change of one molecule represented by an ODE. Weights of the RNN correspond to kinetic parameters in the system and can be adjusted incrementally during network training. The method is applied to the p53-Mdm2 oscillation system - a crucial component of the DNA damage response pathways activated by a damage signal. Simulation results indicate that the proposed RNN can successfully represent the behaviour of the p53-Mdm2 oscillation system and solve the parameter estimation problem with high accuracy. Furthermore, we presented a modified form of the RNN that estimates parameters and captures systems dynamics from sparse data collected over relatively large time steps. We also investigate the robustness of the p53-Mdm2 system using the trained RNN under various levels of parameter perturbation to gain a greater understanding of the control of the p53-Mdm2 system. Its outcomes on robustness are consistent with the current biological knowledge of this system. As more

  13. Synthesis of biological active thiosemicarbazone and characterization of the interaction with human serum albumin

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Wangshu; Shi, Lei; Hui, Guangquan [College of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453007 (China); Cui, Fengling, E-mail: fenglingcui@hotmail.com [College of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453007 (China)

    2013-02-15

    The synthesis of a new biological active reagent, 2-((1,4-dihydroxy)-9,10-anthraquinone) aldehyde thiosemicarbazone (DHAQTS), was designed. The interaction between DHAQTS and HSA was studied by fluorescence spectroscopy in combination with molecular modeling under simulation of physiological conditions. According to the results of fluorescence measurements, the quenching mechanism was suggested to be static. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrophobic interactions are the predominant intermolecular forces stabilizing the complex. The number of binding sites (n) was calculated. Through the site marker competitive experiment, DHAQTS was confirmed to be located in site I of HSA. The binding distance r=2.83 nm between the donor HSA and acceptor DHAQTS was obtained according to Foerster's non-radiative energy transfer theory. The three-dimensional fluorescence spectral results showed the conformation and microenvironment of HSA changed in the presence of DHAQTS. The effects of common ions on the binding of DHAQTS to HSA were also evaluated. The experimental results were in agreement with the results obtained via a molecular docking study. - Highlights: Black-Right-Pointing-Pointer 2-((1,4-dihydroxy)-9,10-anthraquinone)aldehyde thiosemicarbazone (DHAQTS) was synthesized. Black-Right-Pointing-Pointer DHAQTS can quench the fluorescence of human serum albumin (HSA) by static quenching mechanism. Black-Right-Pointing-Pointer Hydrophobic interactions were the predominant intermolecular forces. Black-Right-Pointing-Pointer The competitive experiment was carried out to identify the DHAQTS binding site on HSA. Black-Right-Pointing-Pointer Three-dimensional spectra confirmed DHAQTS caused the conformational change of HSA.

  14. Synthesis of biological active thiosemicarbazone and characterization of the interaction with human serum albumin

    International Nuclear Information System (INIS)

    The synthesis of a new biological active reagent, 2-((1,4-dihydroxy)-9,10-anthraquinone) aldehyde thiosemicarbazone (DHAQTS), was designed. The interaction between DHAQTS and HSA was studied by fluorescence spectroscopy in combination with molecular modeling under simulation of physiological conditions. According to the results of fluorescence measurements, the quenching mechanism was suggested to be static. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrophobic interactions are the predominant intermolecular forces stabilizing the complex. The number of binding sites (n) was calculated. Through the site marker competitive experiment, DHAQTS was confirmed to be located in site I of HSA. The binding distance r=2.83 nm between the donor HSA and acceptor DHAQTS was obtained according to Förster's non-radiative energy transfer theory. The three-dimensional fluorescence spectral results showed the conformation and microenvironment of HSA changed in the presence of DHAQTS. The effects of common ions on the binding of DHAQTS to HSA were also evaluated. The experimental results were in agreement with the results obtained via a molecular docking study. - Highlights: ► 2-((1,4-dihydroxy)-9,10-anthraquinone)aldehyde thiosemicarbazone (DHAQTS) was synthesized. ► DHAQTS can quench the fluorescence of human serum albumin (HSA) by static quenching mechanism. ► Hydrophobic interactions were the predominant intermolecular forces. ► The competitive experiment was carried out to identify the DHAQTS binding site on HSA. ► Three-dimensional spectra confirmed DHAQTS caused the conformational change of HSA.

  15. Comparisons of the interaction of propranolol and timolol with model and biological membrane systems

    Energy Technology Data Exchange (ETDEWEB)

    Herbette, L.; Katz, A.M.; Sturtevant, J.M.

    1983-09-01

    The nonspecific interaction of the beta-adrenergic blocking drugs, propranolol and timolol, with model and biological membranes has been investigated. Radioisotope measurements of the association of these drugs with dimyristoyl lecithin (DMPC) bilayers showed that both propranolol and timolol had a significantly greater molar association (mole of drug per mole of lipid) with DMPC above its phase transition temperature than below. Timolol had a much lower molar association with DMPC as compared with propranolol both above and below the phase transition temperature. For the DMPC model membrane system, the molar association of propranolol as measured by radioisotope and inferred from calorimetric studies was similar. Neutron diffraction utilizing propranolol deuterated in the naphthalene moiety showed that the naphthalene moiety of propranolol partitions into the hydrocarbon core of the DMPC lipid bilayer, and that the charged amine side chain is most likely positioned in the aqueous phospholipid head group region. For timolol, the association as measured by radioisotope methods was apparently greater than the partitioning inferred from calorimetric studies using freezing point depression analysis, suggesting a more complex interaction of timolol as compared with propranolol with the DMPC lipid bilayer. The association of propranolol with the SR membrane (mole of propranolol per mole of SR phospholipid) correlated with its ability to inhibit calcium uptake, whereas only a fraction of the total association of timolol with the SR membrane appeared to lead to inhibition of calcium uptake. Both propranolol and timolol appear to perturb the functional properties of the calcium pump protein in the SR membrane (inhibition of ATP-induced calcium uptake) indirectly by partitioning into the bulk lipid matrix of the SR lipid bilayer, although other sites of interaction cannot be excluded.

  16. Interactive exploration of integrated biological datasets using context-sensitive workflows

    Directory of Open Access Journals (Sweden)

    Fabian eHorn

    2014-02-01

    Full Text Available Network inference utilises experimental high-throughput data for the reconstruction of molecular interaction networks where new relationships between the network entities can be predicted. Despite the increasing amount of experimental data, the parameters of each modelling technique cannot be optimised based on the experimental data alone, but needs to be qualitatively assessed if the components of the resulting network describe the experimental setting. Candidate list prioritisation and validation builds upon data integration and data visualisation. The application of tools supporting this procedure is limited to the exploration of smaller information networks because the display and interpretation of large amounts of information is challenging regarding the computational effort and the users’ experience.The Ondex software framework was extended with customisable context-sensitive menus which allow additional integration and data analysis options for a selected set of candidates during interactive data exploration. We provide new functionalities for on-the-fly data integration using InterProScan, PubMed Central literature search, and sequence-based homology search. We applied the Ondex system to the integration of publicly available data for Aspergillus nidulans and analysed transcriptome data. We demonstrate the advantages of our approach by proposing new hypotheses for the functional annotation of specific genes of differentially expressed fungal gene clusters. Our extension of the Ondex framework makes it possible to overcome the separation between data integration and interactive analysis. More specifically, computationally demanding calculations can be performed on selected sub-networks without losing any information from the whole network. Furthermore, our extensions allow for direct access to online biological databases which helps to keep the integrated information up-to-date.

  17. DeepPIV: Measuring in situ Biological-Fluid Interactions from the Surface to Benthos

    Science.gov (United States)

    Katija, K.; Sherman, A.; Graves, D.; Kecy, C. D.; Klimov, D.; Robison, B. H.

    2015-12-01

    The midwater region of the ocean (below the euphotic zone and above the benthos) is one of the largest ecosystems on our planet, yet it remains one of the least explored. Little known marine organisms that inhabit midwater have developed strategies for swimming and feeding that ultimately contributes to their evolutionary success, and may inspire engineering solutions for societally relevant challenges. Fluid mechanics governs the interactions that midwater organisms have with their physical environment, but limited access to midwater depths and lack of non-invasive methods to measure in situ small-scale fluid motions prevent these interactions from being better understood. Significant advances in underwater vehicle technologies have only recently improved access to midwater. Unfortunately, in situ small-scale fluid mechanics measurement methods are still lacking in the oceanographic community. Here we present DeepPIV, an instrumentation package that can be affixed to remotely operated underwater vehicles that quantifies small-scale fluid motions from the surface of the ocean down to 4000 m depths. Utilizing ambient, suspended particulate in the coastal regions of Monterey Bay, fluid-structure interactions are evaluated on a range of marine organisms in midwater. Initial science targets include larvaceans, biological equivalents of flapping flexible foils, that create mucus houses to filter food. Little is known about the structure of these mucus houses and the function they play in selectively filtering particles, and these dynamics can serve as particle-mucus models for human health. Using DeepPIV, we reveal the complex structures and flows generated within larvacean mucus houses, and elucidate how these structures function.

  18. Chemical Potential Dependence of the Dressed-Quark Propagator from an Effective Quark-Quark Interaction

    Institute of Scientific and Technical Information of China (English)

    ZONG Hong-Shi; PING Jia-Lun; SUN Wei-Min; CHANG Chao-Hsi; WANG Fan

    2002-01-01

    We exhibit a method for obtaining the low chemical potential dependence of the dressed quark propagatorfrom an effective quark-quark interaction model. Within this approach we explore the chemical potential dependenceof the dressed-quark propagator, which provides a means of determining the behavior of the chiral and deconfinementorder parameters. A comparison with the results of previous researches is given.

  19. Soliton-potential interaction in the Nonlinear Klein-Gordon Model

    CERN Document Server

    Saadatmand, Danial

    2011-01-01

    Interaction of solitons with external potentials in nonlinear Klein-Gordon field theory is investigated using an improved model. Presented model is constructed with a better approximation for adding the potential to the lagrangian through the metric of background space-time. The results of the model are compared with the another model and the differences are discussed.

  20. Collisional interactions between self-interacting nonrelativistic boson stars: Effective potential analysis and numerical simulations

    Science.gov (United States)

    Cotner, Eric

    2016-09-01

    Scalar particles are a common prediction of many beyond the Standard Model theories. If they are light and cold enough, there is a possibility they may form Bose-Einstein condensates, which will then become gravitationally bound. These boson stars are solitonic solutions to the Einstein-Klein-Gordon equations but may be approximated in the nonrelativistic regime with a coupled Schrödinger-Poisson system. General properties of single soliton states are derived, including the possibility of quartic self-interactions. Binary collisions between two solitons are then studied, and the effects of different mass ratios, relative phases, self-couplings, and separation distances are characterized, leading to an easy conceptual understanding of how these parameters affect the collision outcome in terms of conservation of energy. Applications to dark matter are discussed.

  1. Phytochemistry, biological activities and potential of annatto in natural colorant production for industrial applications - A review.

    Science.gov (United States)

    Shahid-Ul-Islam; Rather, Luqman J; Mohammad, Faqeer

    2016-05-01

    Bixa orellana commonly known as annatto is one of the oldest known natural dye yielding plants native to Central and South America. Various parts of annatto have been widely used in the traditional medical system for prevention and treatment of a wide number of health disorders. The plethora of traditional uses has encouraged researchers to identify and isolate phytochemicals from all parts of this plant. Carotenoids, apocarotenoids, terpenes, terpenoids, sterols, and aliphatic compounds are main compounds found in all parts of this plant and are reported to exhibit a wide range of pharmacological activities. In recent years annatto has received tremendous scientific interest mainly due to the isolation of yellow-orange natural dye from its seeds which exhibits high biodegradability, low toxicity, and compatibility with the environment. Considerable research work has already been done and is currently underway for its applications in food, textile, leather, cosmetic, solar cells, and other industries. The present review provides up-to-date systematic and organized information on the traditional usage, phytochemistry and pharmacology of annatto. It also highlights its non-food industrial applications in order to bring more interest on this dye plant, identifies the existing gaps and provides potential for future studies. Studies reported in this review have demonstrated that annatto holds a great potential for being exploited as source of drugs and a potential natural dye. However, further efforts are required to identify extract biomolecules and their action mechanisms in exhibiting certain biological activities in order to understand the full phytochemical profile and the complex pharmacological effects of this plant. PMID:27222755

  2. Hydrogen Bonding between Metal-Ion Complexes and Noncoordinated Water: Electrostatic Potentials and Interaction Energies.

    Science.gov (United States)

    Andrić, Jelena M; Misini-Ignjatović, Majda Z; Murray, Jane S; Politzer, Peter; Zarić, Snežana D

    2016-07-01

    The hydrogen bonding of noncoordinated water molecules to each other and to water molecules that are coordinated to metal-ion complexes has been investigated by means of a search of the Cambridge Structural Database (CSD) and through quantum chemical calculations. Tetrahedral and octahedral complexes that were both charged and neutral were studied. A general conclusion is that hydrogen bonds between noncoordinated water and coordinated water are much stronger than those between noncoordinated waters, whereas hydrogen bonds of water molecule in tetrahedral complexes are stronger than in octahedral complexes. We examined the possibility of correlating the computed interaction energies with the most positive electrostatic potentials on the interacting hydrogen atoms prior to interaction and obtained very good correlation. This study illustrates the fact that electrostatic potentials computed for ground-state molecules, prior to interaction, can provide considerable insight into the interactions. PMID:26989883

  3. Natural cures for type 1 diabetes: a review of phytochemicals, biological actions, and clinical potential.

    Science.gov (United States)

    Chang, C L T; Chen, Yi-Ching; Chen, Hui-Ming; Yang, Ning-Sun; Yang, Wen-Chin

    2013-01-01

    Autoimmune diseases are the third largest category of illness in the industrialized world, following cardiovascular diseases and cancers. Among them, type 1 diabetes, also named autoimmune diabetes, afflicts 10 million people worldwide. This disease is caused by autoimmunity-mediated destruction of pancreatic β-cells, leading to insulin deficiency, hyperglycemia and complications. Currently, there is no cure for type 1 diabetes. Insulin injection is the only medication; however, it accompanies serious medical complications. Current strategies to cure type 1 diabetes include immunotherapy, replacement therapy, and combination therapy. Despite recent advances in anti-diabetic strategies, no strategy is clinically successful. How to cure type 1 diabetes without undesirable side effects still remains a formidable challenge in drug research and development. Plants provide an extraordinary source of natural medicines for different diseases. Moreover, secondary metabolites of plant origin serve as an invaluable chemical library for drug discovery and current medicinal chemistry in the pharmaceutical industry. Over the past 25 years, 50% of prescription drugs have been developed from natural products and their derivatives. In this article, we review more than 20 plant compounds and extracts reported in the literature to prevent and treat type-1 diabetes. Emphasis is placed on their chemistry and biology in terms of regulation of immune cells and pancreatic β-cells. We summarize recent progress in understanding the biological actions, mechanisms and therapeutic potential of the compounds and extracts of plant origin in type 1 diabetes. New views on phytocompound-based strategies for prevention and treatment of type 1 diabetes are also discussed. PMID:23210779

  4. The Isolation of DNA by Polycharged Magnetic Particles: An Analysis of the Interaction by Zeta Potential and Particle Size.

    Science.gov (United States)

    Haddad, Yazan; Xhaxhiu, Kledi; Kopel, Pavel; Hynek, David; Zitka, Ondrej; Adam, Vojtech

    2016-04-20

    Magnetic isolation of biological targets is in major demand in the biotechnology industry today. This study considers the interaction of four surface-modified magnetic micro- and nanoparticles with selected DNA fragments. Different surface modifications of nanomaghemite precursors were investigated: MAN37 (silica-coated), MAN127 (polyvinylpyrrolidone-coated), MAN158 (phosphate-coated), and MAN164 (tripolyphosphate-coated). All particles were positive polycharged agglomerated monodispersed systems. Mean particle sizes were 0.48, 2.97, 2.93, and 3.67 μm for MAN37, MAN127, MAN164, and MAN158, respectively. DNA fragments exhibited negative zeta potential of -0.22 mV under binding conditions (high ionic strength, low pH, and dehydration). A decrease in zeta potential of particles upon exposure to DNA was observed with exception of MAN158 particles. The measured particle size of MAN164 particles increased by nearly twofold upon exposure to DNA. Quantitative PCR isolation of DNA with a high retrieval rate was observed by magnetic particles MAN127 and MAN164. Interaction between polycharged magnetic particles and DNA is mediated by various binding mechanisms such as hydrophobic and electrostatic interactions. Future development of DNA isolation technology requires an understanding of the physical and biochemical conditions of this process.

  5. The Isolation of DNA by Polycharged Magnetic Particles: An Analysis of the Interaction by Zeta Potential and Particle Size.

    Science.gov (United States)

    Haddad, Yazan; Xhaxhiu, Kledi; Kopel, Pavel; Hynek, David; Zitka, Ondrej; Adam, Vojtech

    2016-01-01

    Magnetic isolation of biological targets is in major demand in the biotechnology industry today. This study considers the interaction of four surface-modified magnetic micro- and nanoparticles with selected DNA fragments. Different surface modifications of nanomaghemite precursors were investigated: MAN37 (silica-coated), MAN127 (polyvinylpyrrolidone-coated), MAN158 (phosphate-coated), and MAN164 (tripolyphosphate-coated). All particles were positive polycharged agglomerated monodispersed systems. Mean particle sizes were 0.48, 2.97, 2.93, and 3.67 μm for MAN37, MAN127, MAN164, and MAN158, respectively. DNA fragments exhibited negative zeta potential of -0.22 mV under binding conditions (high ionic strength, low pH, and dehydration). A decrease in zeta potential of particles upon exposure to DNA was observed with exception of MAN158 particles. The measured particle size of MAN164 particles increased by nearly twofold upon exposure to DNA. Quantitative PCR isolation of DNA with a high retrieval rate was observed by magnetic particles MAN127 and MAN164. Interaction between polycharged magnetic particles and DNA is mediated by various binding mechanisms such as hydrophobic and electrostatic interactions. Future development of DNA isolation technology requires an understanding of the physical and biochemical conditions of this process. PMID:27104527

  6. Biological and chemical decoration of peptide nanostructures via biotin-avidin interactions.

    Science.gov (United States)

    Reches, Meital; Gazit, Ehud

    2007-07-01

    Novel architectures with nanometric dimensions hold an immense promise as building blocks for future nanotechnological applications. Biological nanostructures are of special interest due to their biocompatibility and because they allow the utilization of biochemical recognition interfaces. The ability to decorate bio-nanostructures with functional groups is highly important in order to utilize them in several applications including ultrasensitive sensors, drug delivery systems, and tissue engineering. Peptide-based nanostructures have a distinct advantage over other assemblies because they can be easily modified with chemical and biological elements. Aromatic dipeptide nanotubes (ADNT) are formed by the self-assembly of a very simple building block, the diphenylalanine peptide. These nanotubes have remarkable chemical and mechanical properties and their utilization in various applications has previously been demonstrated. Here we report on the chemical modification of ADNT with biotin moieties, in order to enable the selective decoration of the tubes with avidin-labeled species. First, ADNT were prepared in aqueous solution by self-assembly of the dipeptide building blocks. Next, they were modified using N-hydroxysuccinimido-biotin. The level of biotinylation was assessed by the interaction of the tubes with gold-labeled strepavidin and ultrastructural analysis by electron microscopy. The ability of the modified assemblies to serve as a generic functional platform was demonstrated by avidin-mediated conjugation. Avidin was added as a molecular linker to allow the decoration with biotin-labeled quantum dots. The efficient decoration was again probed by the imaging of the modified tubes using laser confocal microscopy. Taken together, we demonstrated the ability to decorate ADNT using a generic avidin-biotin adaptor. This decoration should lead to the integration and utilization of the tubes in various applications. PMID:17663236

  7. Fluid Chemistry and Associated Biological Potential in Diverse Serpentinizing Systems of New Zealand’s South Island

    Science.gov (United States)

    Cardace, D.; Hoehler, T.; Foster, A. L.

    2009-12-01

    Serpentinization - the aqueous alteration of ultramafic rocks - generates H2 and other reduced compounds capable of fueling microbial metabolism, and is therefore considered a potential mechanism for the long-term support of subsurface life. This potential may be constrained, however, by rates of serpentinization (corresponding to magnitude of energy flux) and by potentially detrimental co-evolving fluid chemistry - particularly elevated pH. We conducted an initial characterization of the chemistry and associated biological potential of springs and gas seeps associated with two distinct serpentinizing systems in the northwestern Fiordland of New Zealand’s south island. Fluid or gas chemistry, including H2 concentrations, was characterized and used to model energy availability associated with several potential microbial metabolisms; the presence of organisms having targeted metabolisms (methanogenesis, sulfate reduction, iron reduction) was assayed in parallel using quantitative PCR. Serpentinization in Fiordland was tracked in two specific locations. First, the Anita Ultramafites (AU) exposed at Poison Bay are likely ultramafic intrusive rocks within a 3-4 km wide shear zone of deformed gneisses and dunite mylonites (Hill, 1995), which have undergone amphibolite facies metamorphism during continental extension (Gibson, 1990) and now generate gas that escapes from depth along fault networks. Second, along the western edge of the Dun Mountain Ophiolite Belt in the Cascade River Valley, located NW of Milford Sound, deep fluids interact structurally with the Alpine Fault in the ultramafic subsurface; where those fluids escape to the surface, travertine-depositing subaerial springs cover an area of ~100 m2 on a serpentinized talus slope (Aitchison, 1985). Seep fluids from both sites have high pH due to hydroxide solution related to serpentinization, and CaCO3 terraces at the latter site testify to elevated Ca in fluids that reacts with atmospheric CO2 at Earth

  8. Tandem shock waves in medicine and biology: a review of potential applications and successes

    Science.gov (United States)

    Lukes, P.; Fernández, F.; Gutiérrez-Aceves, J.; Fernández, E.; Alvarez, U. M.; Sunka, P.; Loske, A. M.

    2016-01-01

    Shock waves have been established as a safe and effective treatment for a wide range of diseases. Research groups worldwide are working on improving shock wave technology and developing new applications of shock waves to medicine and biology. The passage of a shock wave through soft tissue, fluids, and suspensions containing cells may result in acoustic cavitation i.e., the expansion and violent collapse of microbubbles, which generates secondary shock waves and the emission of microjets of fluid. Cavitation has been recognized as a significant phenomenon that produces both desirable and undesirable biomedical effects. Several studies have shown that cavitation can be controlled by emitting two shock waves that can be delayed by tenths or hundreds of microseconds. These dual-pulse pressure pulses, which are known as tandem shock waves, have been shown to enhance in vitro and in vivo urinary stone fragmentation, cause significant cytotoxic effects in tumor cells, delay tumor growth, enhance the bactericidal effect of shock waves and significantly increase the efficiency of genetic transformations in bacteria and fungi. This article provides an overview of the basic physical principles, methodologies, achievements and potential uses of tandem shock waves to improve biomedical applications.

  9. Real time confocal laser scanning microscopy: Potential applications in space medicine and cell biology

    Science.gov (United States)

    Rollan, Ana; Ward, Thelma; McHale, Anthony P.

    Photodynamic therapy (PDT), in which tissues may be rendered fatally light-sensitive represents a relatively novel treatment for cancer and other disorders such as cardiovascular disease. It offers significant application to disease control in an isolated environment such as space flight. In studying PDT in the laboratory, low energy lasers such as HeNe lasers are used to activate the photosensitized cellular target. A major problem associated with these studies is that events occurring during actual exposure of the target cells to the system cannot be examined in real time. In this study HeLa cells were photosensitized and photodynamic activation was accomplished using the scanning microbeam from a confocal laser scanning microscope. This form of activation allowed for simultaneous photoactivation and observation and facilitated the recording of events at a microscopic level during photoactivation. Effects of photodynamic activation on the target cells were monitored using the fluorophores rhodamine 123 and ethidium homodimer-1. Potential applications of these forms of analyses to space medicine and cell biology are discussed.

  10. The potential for biologically catalyzed anaerobic methane oxidation on ancient Mars.

    Science.gov (United States)

    Marlow, Jeffrey J; Larowe, Douglas E; Ehlmann, Bethany L; Amend, Jan P; Orphan, Victoria J

    2014-04-01

    This study examines the potential for the biologically mediated anaerobic oxidation of methane (AOM) coupled to sulfate reduction on ancient Mars. Seven distinct fluids representative of putative martian groundwater were used to calculate Gibbs energy values in the presence of dissolved methane under a range of atmospheric CO2 partial pressures. In all scenarios, AOM is exergonic, ranging from -31 to -135 kJ/mol CH4. A reaction transport model was constructed to examine how environmentally relevant parameters such as advection velocity, reactant concentrations, and biomass production rate affect the spatial and temporal dependences of AOM reaction rates. Two geologically supported models for ancient martian AOM are presented: a sulfate-rich groundwater with methane produced from serpentinization by-products, and acid-sulfate fluids with methane from basalt alteration. The simulations presented in this study indicate that AOM could have been a feasible metabolism on ancient Mars, and fossil or isotopic evidence of this metabolic pathway may persist beneath the surface and in surface exposures of eroded ancient terrains.

  11. Parasitoid Guilds of Agrilus Woodborers (Coleoptera: Buprestidae: Their Diversity and Potential for Use in Biological Control

    Directory of Open Access Journals (Sweden)

    Philip B. Taylor

    2012-01-01

    Full Text Available Literature studies in North America (US and Canada, Europe, and Asia (particularly Russia, China, Japan, and the Korean peninsula were reviewed to identify parasitoid guilds associated with Agrilus woodborers. There are at least 12 species of hymenopteran parasitoids attacking eggs of Agrilus beetles and 56 species (36 genera, attacking Agrilus larvae infesting various host plants in North America, Asia, and Europe. While most of the egg parasitoids (9 species belong to the family Encyrtidae, a majority of the larval parasitoids are members of five families: Braconidae (24 species/11 genera, Eulophidae (8 species/4 genera, Ichneumonidae (10 species/9 genera, and Eupelmidae (6 species/5 genera. The highest rate of Agrilus egg parasitism (>50% was exerted by encyrtid wasps (4 species in North America, Asia, and Europe. In contrast, the highest rate of Agrilus larval parasitism (>50% was caused by species in two genera of braconids: Atanycolus (North America and Spathius (Asia, and one eulophid genus, Tetrastichus (Asia and Europe. Reported rate of Agrilus larval parasitism ichneumonids was frequent in North America, but generally low (<1%. Potential for success in biological control of emerald ash borer (Agrilus planipennis Fairmaire in the USA with North American native parasitoids and old-association Asian parasitoids is discussed.

  12. SiC nanoparticles as potential carriers for biologically active substances

    Science.gov (United States)

    Guevara-Lora, Ibeth; Czosnek, Cezary; Smycz, Aleksandra; Janik, Jerzy F.; Kozik, Andrzej

    2009-01-01

    Silicon carbide SiC thanks to its many advantageous properties has found numerous applications in diverse areas of technology. In this regard, its nanosized forms often with novel properties have been the subject of intense research in recent years. The aim of this study was to investigate the binding of biologically active substances onto SiC nanopowders as a new approach to biomolecule immobilization in terms of their prospective applications in medicine or for biochemical detection. The SiC nanoparticles were prepared by a two-stage aerosol-assisted synthesis from neat hexamethyldisiloxane. The binding of several proteins (bovine serum albumin, high molecular weight kininogen, immunoglobulin G) on SiC particle surfaces was demonstrated at the levels of 1-2 nanograms per mg of SiC. These values were found to significantly increase after suitable chemical modifications of nanoparticle surfaces (by carbodiimide or 3-aminopropyltrietoxysilane treatment). The study of SiC biocompatibility showed a lack of cytotoxicity against macrophages-like cells below the concentration of 1 mg nanoparticles per mL. In summary, we demonstrated the successful immobilization of the selected substances on the SiC nanoparticles. These results including the cytotoxicity study make nano-SiC highly attractive for potential applications in medicine, biotechnology or molecular detection.

  13. Potential role of lncRNA cyp2c91-protein interactions on diseases of the immune system.

    Science.gov (United States)

    Suravajhala, Prashanth; Kogelman, Lisette J A; Mazzoni, Gianluca; Kadarmideen, Haja N

    2015-01-01

    With unprecedented increase in next generation sequencing technologies, there has been a persistent interest on transcript profiles of long non-coding RNAs (lncRNAs) and protein-coding genes forming an interaction network. Apart from protein-protein interaction (PPI), gene network models such as Weighted Gene Co-expression Network Analysis (WGCNA) are used to functionally annotate lncRNAs in identifying their potential disease associations. To address this, studies have led to characterizing transcript structures and understanding expression profiles mediating regulatory roles. In the current exploratory analysis, we show how a lncRNA - cyp2c91 contributes to the transcriptional regulation localized to cytoplasm thereby making refractory environment for transcription. By applying network methods and pathway analyses on genes related to a disease such as obesity and systemic lupus erythematosus, we show that we can gain deeper insight in biological processes such as the perturbances in immune system, and get a better understanding of the systems biology of diseases. PMID:26284111

  14. Potential role of lncRNA cyp2c91-protein interactions on diseases of the immune system

    Directory of Open Access Journals (Sweden)

    Prashanth eSuravajhala

    2015-07-01

    Full Text Available With unprecedented increase in next generation sequencing (NGS technologies, there has been a persistent interest on transcript profiles of long noncoding RNAs (lncRNAs and protein-coding genes forming an interaction network. Apart from protein-protein interaction (PPI, gene network models such as Weighted Gene Co-expression Network Analysis are used to functionally annotate lncRNAs in identifying their potential disease associations. To address this, studies have led to characterizing transcript structures and understanding expression profiles mediating regulatory roles. In the current exploratory analysis, we show how a lncRNA - cyp2c91 contributes to the transcriptional regulation localized to cytoplasm thereby making refractory environment for transcription. By applying network methods and pathway analyses on genes related to a disease such as obesity and systemic lupus erythematosus, we show that we can gain deeper insight in biological processes such as the perturbances in immune system, and get a better understanding of the systems biology of diseases.

  15. Interaction of hepatitis B virus with tumor suppressor gene p53: its significance and biological function

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The mechanism of the interaction of hepatitis B virus (HBV) with tumor suppressor p53 and its role in the hepatocarcinogenesis have been studied by PCR-directed sequencing, gel shift assays and in situ ultraviolet cross-linking assay. The biological function of the interaction of HBV with p53 gene was investigated by co-transfection of chloramphenicol acetyltransferase (CAT) reporter gene, p53 and HBV DNA, and quantitative PCR. Among the 16 primary hepatocellular carcinoma (PHC) samples, 13 were HBV-DNA positive,10 HBxAg positive and 9 p53 protein positive. The p53 gene point mutation was found in 5 samples, one of which had a G to T substitution located at codon 249. After analyzing the HBV genome by a computer program, a p53 response element binding sequence was found in HBV genome at upstream of enhancer I, from 1047 to 1059 nucleotides. This sequence could specifically bind to p53 protein, increase p53 protein accumulation in the PHC cells and stimulate the transactivating activity of p53 and HBV replication .The results also revealed that HBxAg could combine with p53 protein to form a complex in the cells and enhance CAT expression. Immunocytochemical staining showed that p53 protein complex was located in the cytoplasm and the process of p53 entry to nuclei was, in part, blocked. From our results, we conclude that the mutation of p53 gene at codon 249 is infrequent in HBV-associated PHC, the DNA-protein binding between HBV and p53, and the protein-protein binding between HBxAg and p53 might lead to the reduction or inactivation of p53 protein, which in turn resulting in HBV-associated hepatocarcinogenesis.

  16. The potential use of online tools for scientific collaboration by biology researchers

    OpenAIRE

    Bracken, Fintan; Earls, Daniel; Madders, Catherine; O'Leary, Faye; Ronan, Stephanie; Ward, Ciara; Tolan, Paul; Wusteman, Judith

    2014-01-01

    Purpose - The purpose of this paper is to discover the research practices of biology researchers and to assess the suitability of the OJAX++ Virtual Research Environment (VRE) for these researchers. Design/methodology/approach â Usability testing was used to evaluate the usability of OJAX++ in relation to biology researchers. Interviews with biology researchers in a large Irish university were conducted to investigate their research information behaviour, to establish user requirements ...

  17. Mitochondrial DNA mapping of social-biological interactions in Brazilian Amazonian African-descendant populations

    Directory of Open Access Journals (Sweden)

    Bruno Maia Carvalho

    2008-01-01

    Full Text Available The formation of the Brazilian Amazonian population has historically involved three main ethnic groups, Amerindian, African and European. This has resulted in genetic investigations having been carried out using classical polymorphisms and molecular markers. To better understand the genetic variability and the micro-evolutionary processes acting in human groups in the Brazilian Amazon region we used mitochondrial DNA to investigate 159 maternally unrelated individuals from five Amazonian African-descendant communities. The mitochondrial lineage distribution indicated a contribution of 50.2% from Africans (L0, L1, L2, and L3, 46.6% from Amerindians (haplogroups A, B, C and D and a small European contribution of 1.3%. These results indicated high genetic diversity in the Amerindian and African lineage groups, suggesting that the Brazilian Amazonian African-descendant populations reflect a possible population amalgamation of Amerindian women from different Amazonian indigenous tribes and African women from different geographic regions of Africa who had been brought to Brazil as slaves. The present study partially mapped the historical biological and social interactions that had occurred during the formation and expansion of Amazonian African-descendant communities.

  18. Effects of transforming growth interacting factor on biological behaviors of gastric carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Zhong-Liang Hu; Ji-Fang Wen; De-Sheng Xiao; Hui Zhen; Chun-Yan Fu

    2005-01-01

    AIM:Transforming growth interacting factor (TGIF) is an inhibitor of both transforming growth factor β (TGF-β) and retinoid signaling pathways. Moreover, the activation of MAPK pathway can prolong its half-life. However, its role in carcinogenesis is still unknown. Thus we attempted to investigate the effect of TGIF on biologic behaviors of gastric carcinoma cells.METHODS: Gastric carcinoma cell line, SGC-7901, was stably transfected with plasmid PcDNA3.1-TGIF. Western blotting and cell immunohistochemistry screening for the highly expressing clone of TGIF were employed. The growth of transfected cells was investigated by MTT and colonyformation assays, and apoptosis was measured by flow cytometry (FCM) and transmission electron microscopy.Tumorigenicity of the transfectant cells was also analyzed.RESULTS: TGIF had no effect on the proliferation, cell cycle and apoptosis of SGC-7901 cells, but cellular organelles of cells transfected with TGIF were richer than those of vector control or parental cells. Its clones were smaller than the control ones in plate efficiency, and its tumor tissues also had no obvious necrosis compared with the vector control or parental cells. Moreover, TGIF could resist TGF-β mediated growth inhibition.CONCLUSION: TGIF may induce differentiation of stomach neoplastic cells. In addition, TGIF can counteract the growth inhibition induced by TGF-β.

  19. Neutron Reflectometry Investigations of the Interaction of DNA-PAMAM Dendrimers with Model Biological Membranes

    International Nuclear Information System (INIS)

    The systemic delivery of DNA for gene therapy requires control of DNA compaction by an agent, such a lipid, surfactant or a polymer (e.g. cationic dendrimers) as well as understanding of how this complex interacts with a biological membrane. Poly (amido amine) (PAMAM) dendrimers have been reported to be a promising synthetic gene-transfection agent. We have studied the structure of the complexes formed between DNA and PAMAM dendrimers with SANS, dynamic light scattering and cryo-TEM. Here we noted that the structure of the complex formed strongly depends on the generation of the dendrimer. The results of the adsorption of generation 2 (G2) and 4 (G4) PAMAM dendrimers to surface deposited bilayers, consisting of palmitoyl oleoyl phosphatidyl choline on silicon surface, have been studied using neutron reflectometry (NR). The NR data shows that the dendrimers are able to penetrate the bilayer. However, the complex is less able to penetrate the bilayer, but rather stays on the top of the bilayer. The dendrimers appear slightly flattened on the surface in comparison with their size in bulk as determined by light scattering. We will also report on the interfacial behavior of the DNA-PAMAM complexes at other types of studies of interfaces, important for biomedical applications, where NR has allowed us to determine the layer structure and composition. (author)

  20. Interactive Software for the study of membrane biology: lipid composition, solubilization and liposome reconstitution and characterization

    Directory of Open Access Journals (Sweden)

    I.A. Borin

    2006-07-01

    Full Text Available Biological  membranes define cellular boundaries, divide cells into discrete  compartments, organize complex reaction sequences, and act in signal reception and energy transformations. This topic is studied in all undergraduate biochemistry  courses.  Visualization  of  structures  generally  facilitates  the  understanding  of  many  related  topics  of membrane composition, structures, and protein interactions but they lack in many events that occurs in membranes. Also,  at  the  present  time,  animations  exploring  solubilization  and  reconstitution  of  membrane  proteins  in  vesicular systems are not available. Thus, we have developed a software  named  AnimaBio, in Macromedia  Flash 7.0, whose principal objective was the animation of some  processes  used  in the study  of membrane  biology and it was  didactically  divided  in:  (1 composition  and  physics  properties;  (2  construction  of  systems  mimetically  to  natural  membranes  and  (3 characterization of these biomimetic systems using experimental examples.The topics explained in each section were: (1 Membranes composition; lipids and proteins distribution; fluid mosaic  model;  the  basic  structural  unit  of  lipid  bilayer;  peripheral  proteins;  anchored  proteins;  integral  proteins; covalently attached oligosaccharides; solubilization of proteins and hemolytic effects; (2 construction of biomimetical systems using different techniques; sonication followed by direct insertion of proteins and co-solubilization methods; (3  Kinetic  properties  of  the  enzyme,  reconstituted  in  the  vesicular  system,  using  examples  of  actions  of  different agents such as: inhibitors, detergents, ionophores and photosensitive dyes. All topics were illustrated in the animation using  some  examples  such  as:  erythrocytes  membranes;  alkaline  phosphatase  (which

  1. Host-pathogen Interaction at the Intestinal Mucosa Correlates With Zoonotic Potential of Streptococcus suis

    DEFF Research Database (Denmark)

    Ferrando, Maria Laura; de Greeff, Astrid; van Rooijen, Willemien J. M.;

    2015-01-01

    of SS2 infection. Methods. We developed a noninvasive in vivo model to study oral SS2 infection in piglets. We compared in vitro interaction of S. suis with human and porcine intestinal epithelial cells (IEC). Results. Two out of 15 piglets showed clinical symptoms compatible with S. suis infection 24...... be considered a food-borne pathogen. S. suis interaction with human and pig IEC correlates with S. suis serotype and genotype, which can explain the zoonotic potential of SS2....

  2. Study the Effectiveness of Technology-Enhanced Interactive Teaching Environment on Student Learning of Junior High School Biology

    Science.gov (United States)

    Yang, Kai-Ti; Wang, Tzu-Hua; Chiu, Mei-Hung

    2015-01-01

    This research investigates the effectiveness of integrating Interactive Whiteboard (IWB) into the junior high school biology teaching. This research adopts a quasi-experimental design and divides the participating students into the conventional ICT-integrated learning environment and IWB-integrated learning environment. Before teaching, students…

  3. Equation of state and interaction potential of helium under high temperatures and high densities

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Based on the thermodynamics statistic method, the improved variational perturbation theory and the modified quantum mechanics correction model have been used to calculate the equation of state of liquid helium at pressure from 0.7 to 108 GPa. The calculation results are in good agreement with the experimental data. The EXP-6 potential (α = 13.1) can more accurately describe the interaction of helium atoms than other potentials in the scheme. Finally, a comparison is shown between our interatomic potentials and other potentials.

  4. Equation of state and interaction potential of helium under high temperatures and high densities

    Institute of Scientific and Technical Information of China (English)

    YANG JinWen; YAN YuanHong

    2009-01-01

    Based on the thermodynamics statistic method, the improved variational perturbation theory and the modified quantum mechanics correction model have been used to calculate the equation of state of liquid helium at pressure from 0.7 to 108 GPa. The calculation results are in good agreement with the experimental data. The EXP-6 potential (α=13.1) can more accurately describe the interaction of helium atoms than other potentials in the scheme. Finally, s comparison is shown between our interatomic potentials and other potentials.

  5. The dynamical behaviour of homogeneous scalar-field spacetimes with general self-interaction potentials

    CERN Document Server

    Giambó, Roberto; Magli, Giulio

    2008-01-01

    The dynamics of homogeneous Robertson--Walker cosmological models with a self-interacting scalar field source is examined here in full generality, requiring only the scalar field potential to be bounded from below and divergent when the field diverges. In this way we are able to give a unified treatment of all the already studied cases - such as positive potentials which exhibit asymptotically polynomial or exponential behaviors - together with its extension to a much wider set of physically sensible potentials. Since the set includes potentials with negative inferior bound, we are able to give, in particular, the analysis of the asymptotically anti De Sitter states for such cosmologies.

  6. Intermolecular interaction potentials of methane-argon complex calculated using LDA approaches

    Institute of Scientific and Technical Information of China (English)

    Bai Yu-Lin; Chen Xiang-Rong; Zhou Xiao-Lin; Yang Xiang-Dong; Wang Hai-Yan

    2004-01-01

    The intermolecular interaction potential for methane-argon complex is calculated by local density approximation (LDA) approaches. The calculated potential has a minimum when the intermolecular distance of methane-argon complex is 6.75 a.u.; the corresponding depth of the potential is 0.0163eV which has good agreement with experimental data. We also have made a nonlinear fitting of our results for the Lennard-Jones (12-6) potential function and obtain that V(R) = 143794365.332/R12 - 3032.093/R6 (R in a.u. and V(R) in eV).

  7. Evaluation of the Interaction between the Poincianella pyramidalis (Tul. LP Queiroz Extract and Antimicrobials Using Biological and Analytical Models.

    Directory of Open Access Journals (Sweden)

    Thiago P Chaves

    Full Text Available Poincianella pyramidalis (Tul. LP Queiroz (Fabaceae is an endemic tree of northeastern Brazil, occurring mainly in the Caatinga. Its medicinal use is widespread and is an important therapeutic option against diarrhea, dysentery, and respiratory and urinary infections, among other diseases. In this study we determined the chemical marker and evaluated the interaction between P. pyramidalis extract and a commercial antimicrobial through the use of biological and analytical models. To obtain the extract, an ethanol-water mixture (50:50 v/v was used as solvent. It was nebulized in a spray dryer using colloidal silicon dioxide as a drying adjuvant. The extract (ENPp was subjected to HPLC analysis to verify the presence of certain secondary metabolites. The Minimum Inhibitory Concentration (MIC of the extract against Gram-negative bacteria was determined by broth microdilution and the MIC of synthetic antimicrobial drugs in the presence and absence of the extract. The antioxidant activity of ENPp was evaluated by the DPPH method. The compatibility between the antimicrobial and the extract was evaluated by thermal analysis (TG/DTA. The acute toxicity of the extract was evaluated in vivo in rodents. The results indicate significant additive action of the extract on synthetic antibiotics, considerable antioxidant activity and absence of toxicity. This extract shows high potential for the development of formulations for antimicrobial therapy when used with a vegetable-active ingredient.

  8. Evaluation of the Interaction between the Poincianella pyramidalis (Tul.) LP Queiroz Extract and Antimicrobials Using Biological and Analytical Models

    Science.gov (United States)

    Santana, Cleildo P.; Medeiros, Francinalva D.; Felismino, Délcio C.; Santos, Vanda L.; Catão, Raïssa Mayer R.; Coutinho, Henrique Douglas M.

    2016-01-01

    Poincianella pyramidalis (Tul.) LP Queiroz (Fabaceae) is an endemic tree of northeastern Brazil, occurring mainly in the Caatinga. Its medicinal use is widespread and is an important therapeutic option against diarrhea, dysentery, and respiratory and urinary infections, among other diseases. In this study we determined the chemical marker and evaluated the interaction between P. pyramidalis extract and a commercial antimicrobial through the use of biological and analytical models. To obtain the extract, an ethanol-water mixture (50:50 v/v) was used as solvent. It was nebulized in a spray dryer using colloidal silicon dioxide as a drying adjuvant. The extract (ENPp) was subjected to HPLC analysis to verify the presence of certain secondary metabolites. The Minimum Inhibitory Concentration (MIC) of the extract against Gram-negative bacteria was determined by broth microdilution and the MIC of synthetic antimicrobial drugs in the presence and absence of the extract. The antioxidant activity of ENPp was evaluated by the DPPH method. The compatibility between the antimicrobial and the extract was evaluated by thermal analysis (TG/DTA). The acute toxicity of the extract was evaluated in vivo in rodents. The results indicate significant additive action of the extract on synthetic antibiotics, considerable antioxidant activity and absence of toxicity. This extract shows high potential for the development of formulations for antimicrobial therapy when used with a vegetable-active ingredient. PMID:27192209

  9. Temperature-dependent optical potential and mean free path based on Skyrme interactions

    International Nuclear Information System (INIS)

    Optical potentials and mean free paths of nucleons at finite temperatures are studied by utilizing effective Skyrme interactions which yield 'good' optical potentials at zero temperature. The results for nuclear matter (symmetric and asymmetric) are applied within the local density approximation of finite nuclei at various temperatures. Because of the limitation due to zero-range forces used and the assumptions of temperature independent nuclear densities and effective Skyrme interactions made, the calculations are expected to be limited to nucleon energies between 10 and 50 MeV above the Fermi energy and to nuclear temperatures of less than 8 MeV. (orig.)

  10. A Riccati equation based approach to isotropic scalar field cosmologies with arbitrary self-interaction potentials

    CERN Document Server

    Harko, Tiberiu; Mak, M K

    2014-01-01

    Gravitationally coupled scalar fields $\\phi $, distinguished by the choice of an effective self-interaction potential $V(\\phi )$, simulating a temporarily non-vanishing cosmological term, can generate both inflation and late time acceleration. In scalar field cosmological models the evolution of the Hubble function is determined, in terms of the interaction potential, by a Riccati type equation. In the present work we investigate scalar field cosmological models that can be obtained as solutions of the Riccati evolution equation for the Hubble function. Four exact integrability cases of the field equations are presented, representing classes of general solutions of the Riccati evolution equation, and their cosmological properties are investigated in detail.

  11. Potential herbs and herbal nutraceuticals: food applications and their interactions with food components.

    Science.gov (United States)

    Hussain, Shaik Abdul; Panjagari, Narender Raju; Singh, R R B; Patil, G R

    2015-01-01

    Since ancient times, herbs have been used as natural remedies for curing many physiological disorders. Traditional medicinal literature appreciated their value as nature's gift to mankind for the healing of illnesses. Some of the herbs have also been used for culinary purposes, and few of them have been used in cheese manufacture both as coagulating agents and flavor ingredients. Scientific investigations regarding biological activity and toxicity of chemical moieties present in many herbs have been carried out over a period of time. Consequently, literature related to the use of herbs or their functional ingredients in foods and their interaction with food constituents has been appearing in recent times. This article presents the information regarding some biologically active constituents occurring in commonly used herbs, viz., alkaloids, anthraquinones, bitters, flavonoids, saponins, tannins, and essential oils, their physiological functionalities, and also the description of few herbs of importance, viz., Asparagus racemosus, Withania somnifera, Bacopa monniera, Pueraria tuberose, Emblica officinalis, Terminalia chebula, Terminalia belerica, Terminalia arjuna, and Aloe vera, in terms of their chemical composition, biological functionality, and toxicity. This article also reviews the use of herbs and their active ingredients in foods and their interactions with different food constituents. PMID:24915396

  12. Mean field propagation of infinite dimensional Wigner measures with a singular two-body interaction potential

    OpenAIRE

    AMMARI, Zied; Nier, Francis

    2015-01-01

    49 pages International audience We consider the quantum dynamics of many bosons systems in the mean field limit with a singular pair-interaction potential, including the attractive or repulsive Coulombic case in three dimensions. By using a measure transportation technique, we show that Wigner measures propagate along the nonlinear Hartree flow. Such property was previously proved only for bounded potentials in our previous works with a slightly different strategy.

  13. Mean field propagation of infinite dimensional Wigner measures with a singular two-body interaction potential

    CERN Document Server

    Ammari, Zied

    2011-01-01

    We consider the quantum dynamics of many bosons systems in the mean field limit with a singular pair-interaction potential, including the attractive or repulsive Coulombic case in three dimensions. By using a measure transportation technique, we show that Wigner measures propagate along the nonlinear Hartree flow. Such property was previously proved only for bounded potentials in our previous works with a slightly different strategy.

  14. Interacting particles in a periodically moving potential: Traveling wave and transport

    OpenAIRE

    Chatterjee, Rakesh; Chatterjee, Sakuntala; Pradhan, Punyabrata; Manna, S.S.

    2014-01-01

    We study a system of interacting particles in a periodically moving external potential, within the simplest possible description of paradigmatic symmetric exclusion process on a ring. The model describes diffusion of hardcore particles where the diffusion dynamics is locally modified at a uniformly moving defect site, mimicking the effect of the periodically moving external potential. The model, though simple, exhibits remarkably rich features in particle transport, such as polarity reversal ...

  15. A review of potential harmful interactions between anticoagulant/antiplatelet agents and Chinese herbal medicines.

    Directory of Open Access Journals (Sweden)

    Hsin-Hui Tsai

    Full Text Available BACKGROUND: The risks attributed to drug-herb interactions, even when known, are often ignored or underestimated, especially for those involving anti-clotting drugs and Chinese medicines. The aim of this study was to structurally search and evaluate the existing evidence-based data associated with potential drug interactions between anticoagulant/antiplatelet drugs and Chinese herbal medicines (CHMs and evaluate the documented mechanisms, consequences, and/or severity of interactions. METHODOLOGY AND FINDINGS: Information related to anticoagulant/antiplatelet drug-CHM interactions was retrieved from eight interaction-based textbooks, four web resources and available primary biomedical literature. The primary literature searches were conducted in English and/or Chinese from January 2000 through December 2011 using the secondary databases (e.g., PubMed, Airiti Library, China Journal full-text database. The search terms included the corresponding medical subject headings and key words. Herbs or natural products not used as a single entity CHM or in Chinese Medicinal Prescriptions were excluded from further review. The corresponding mechanisms and severity ratings of interactions were retrieved using MicroMedex®, Lexicomp® and Natural Medicines Comprehensive Database®. Finally, we found 90 single entity CHMs contributed to 306 documented drug-CHM interactions. A total of 194 (63.4% interactions were verified for its evidence describing possible mechanisms and severity. Of them, 155 interactions (79.9% were attributable to pharmacodynamic interactions, and almost all were rated as moderate to severe interactions. The major consequences of these interactions were increased bleeding risks due to the additive anticoagulant or antiplatelet effects of the CHMs, specifically danshen, dong quai, ginger, ginkgo, licorice, and turmeric. CONCLUSIONS/SIGNIFICANCE: Conventional anticoagulants and antiplatelet drugs were documented to have harmful interactions

  16. Whole-Genome Sequence of Pseudomonas graminis Strain UASWS1507, a Potential Biological Control Agent and Biofertilizer Isolated in Switzerland

    Science.gov (United States)

    Crovadore, Julien; Calmin, Gautier; Chablais, Romain; Cochard, Bastien; Schulz, Torsten

    2016-01-01

    We report here the whole-genome shotgun sequence of the strain UASWS1507 of the species Pseudomonas graminis, isolated in Switzerland from an apple tree. This is the first genome registered for this species, which is considered as a potential and valuable resource of biological control agents and biofertilizers for agriculture.

  17. Multicomponent click synthesis of potentially biologically active triazoles catalysed by copper nanoparticles on activated carbon in water

    OpenAIRE

    Alonso Valdés, Francisco; Moglie, Yanina; Radivoy, Gabriel; Yus Astiz, Miguel

    2011-01-01

    A variety of potentially biologically active 1,2,3-triazoles, derived from (–)-menthol, lactic acid, D-glucose, oestrone, cholesterol, and phenacetin, have been synthesised through the multicomponent alkyne-azide 1,3-dipolar cycloaddition catalysed by copper nanoparticles on activated carbon in neat water.

  18. Strategies for structuring interdisciplinary education in Systems Biology

    DEFF Research Database (Denmark)

    Cvijovic, Marija; Höfer, Thomas; Aćimović, Jure;

    2016-01-01

    Systems Biology is an approach to biology and medicine that has the potential to lead to a better understanding of how biological properties emerge from the interaction of genes, proteins, molecules, cells and organisms. The approach aims at elucidating how these interactions govern biological fu...

  19. After the Greeting: Realizing the Potential of Physical Models in Cell Biology.

    Science.gov (United States)

    Paluch, Ewa K

    2015-12-01

    Biophysics is increasingly taking center stage in cell biology as the tools for precise quantifications of cellular behaviors expand. Interdisciplinary approaches, combining quantitative physical modeling with cell biology, are of growing interest to journal editors, funding agencies, and hiring committees. However, despite an ever-increasing emphasis on the importance of interdisciplinary research, the student trained in biology may still be at a loss as to what it actually means. I discuss here some considerations on how to achieve meaningful and high-quality interdisciplinary work.

  20. Physical interaction between SLX4 (FANCP) and XPF (FANCQ) proteins and biological consequences of interaction-defective missense mutations.

    Science.gov (United States)

    Hashimoto, Keiji; Wada, Kunio; Matsumoto, Kyomu; Moriya, Masaaki

    2015-11-01

    SLX4 (FANCP) and XPF (FANCQ) proteins interact with each other and play a vital role in the Fanconi anemia (FA) DNA repair pathway. We have identified a SLX4 region and several amino acid residues that are responsible for this interaction. The study has revealed that the global minor allele, SLX4(Y546C), is defective in this interaction and cannot complement Fancp knockout mouse cells in mitomycin C-induced cytotoxicity or chromosomal aberrations. These results highly suggest this allele, as well as SLX4(L530Q), to be pathogenic. The interacting partner XPF is involved in various DNA repair pathways, and certain XPF mutations cause progeria, Cockayne syndrome (CS), and/or FA phenotypes. Because several atypical xeroderma pigmentosum (XP) phenotype-causing XPF missense mutations are located in the SLX4-interacting region, we suspected the disruption of the interaction with SLX4 in these XPF mutants, thereby causing severer phenotypes. The immunoprecipitation assay of cell extracts revealed that those XPF mutations, except XPF(C236R), located in the SLX4-interacting region cause instability of XPF protein, which could be the reason for the FA, progeria and/or CS phenotypes. PMID:26453996

  1. The potential of protein-nanomaterial interaction for advanced drug delivery.

    Science.gov (United States)

    Peng, Qiang; Mu, Huiling

    2016-03-10

    Nanomaterials, like nanoparticles, micelles, nano-sheets, nanotubes and quantum dots, have great potentials in biomedical fields. However, their delivery is highly limited by the formation of protein corona upon interaction with endogenous proteins. This new identity, instead of nanomaterial itself, would be the real substance the organs and cells firstly encounter. Consequently, the behavior of nanomaterials in vivo is uncontrollable and some undesired effects may occur, like rapid clearance from blood stream; risk of capillary blockage; loss of targeting capacity; and potential toxicity. Therefore, protein-nanomaterial interaction is a great challenge for nanomaterial systems and should be inhibited. However, this interaction can also be used to functionalize nanomaterials by forming a selected protein corona. Unlike other decoration using exogenous molecules, nanomaterials functionalized by selected protein corona using endogenous proteins would have greater promise for clinical use. In this review, we aim to provide a comprehensive understanding of protein-nanomaterial interaction. Importantly, a discussion about how to use such interaction is launched and some possible applications of such interaction for advanced drug delivery are presented.

  2. The potential of protein-nanomaterial interaction for advanced drug delivery.

    Science.gov (United States)

    Peng, Qiang; Mu, Huiling

    2016-03-10

    Nanomaterials, like nanoparticles, micelles, nano-sheets, nanotubes and quantum dots, have great potentials in biomedical fields. However, their delivery is highly limited by the formation of protein corona upon interaction with endogenous proteins. This new identity, instead of nanomaterial itself, would be the real substance the organs and cells firstly encounter. Consequently, the behavior of nanomaterials in vivo is uncontrollable and some undesired effects may occur, like rapid clearance from blood stream; risk of capillary blockage; loss of targeting capacity; and potential toxicity. Therefore, protein-nanomaterial interaction is a great challenge for nanomaterial systems and should be inhibited. However, this interaction can also be used to functionalize nanomaterials by forming a selected protein corona. Unlike other decoration using exogenous molecules, nanomaterials functionalized by selected protein corona using endogenous proteins would have greater promise for clinical use. In this review, we aim to provide a comprehensive understanding of protein-nanomaterial interaction. Importantly, a discussion about how to use such interaction is launched and some possible applications of such interaction for advanced drug delivery are presented. PMID:26812004

  3. Optical model potential in the lowest order Brueckner theory and complex effective N-N interaction

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Norio; Nagata, Sinobu; Matsuda, Takaaki.

    1983-08-01

    The optical model potential for a nucleon propagating inside the infinite nuclear medium is calculated in the Brueckner-Hartree-Fock approximation. It is found that the resultant optical potential, especially its imaginary part, strongly depends on the strength of the tensor component and the short-range behavior of the used realistic nuclear force. Our results for the real part show a large anomaly just above the Fermi momentum especially in lower density. This anomaly mainly comes from the /sup 3/S/sub 1/ + /sup 3/D/sub 1/ state interaction. From the obtained transition matrix a complex effective N-N interaction with three-range-Gaussian form factor is constructed. This interaction reproduces the partial wave contributions to the optical potential in nuclear matter. By using the folding procedure, this effective interaction is applied to the p+/sup 40/Ca elastic scattering. The observed differential cross section and polarization are very well reproduced over a wide range of energies with only a renormalization of the imaginary potential strength. (author).

  4. On Local Smooth Solutions for the Vlasov Equation with the Potential of Interactions {\\pm} r^{-2}

    CERN Document Server

    Zhidkov, P E

    2003-01-01

    For the initial value problem for the Vlasov equation with the potential of interactions {\\pm} r^{-2} we prove the existence and uniqueness of a local solution with values in the Schwartz space S of infinitely differentiable functions rapidly decaying at infinity.

  5. Critical temperature of Bose-Einstein condensation for weakly interacting bose gas in a potential trap

    Institute of Scientific and Technical Information of China (English)

    YU; Xuecai; YE; Yutang; WU; Yunfeng; XIE; Kang; CHENG; Lin

    2005-01-01

    The critical temperature of Bose-Einstein condensation at minimum momentum state for weakly interacting Bose gases in a power-law potential and the deviation of the critical temperature from ideal bose gas are studied. The effect of interaction on the critical temperature is ascribed to the ratiao α/λc, where α is the scattering length for s wave and λc is de Broglie wavelength at critical temperature. As α/λc<<1/(2π)2, the interaction is negligible. The presented deviation of the critical temperature for three dimensional harmonic potential is well in agreement with recent measurement of critical temperature for 87Rb bose gas trapped in a harmonic well.

  6. Hydrologic and biologic influences on stream network nutrient concentrations: Interactions of hydrologic turnover and concentration-dependent nutrient uptake

    Science.gov (United States)

    Mallard, John; McGlynn, Brian; Covino, Tim

    2016-04-01

    Stream networks lie in a crucial landscape position between terrestrial ecosystems and downstream water bodies. As such, whether inferring terrestrial watershed processes from watershed outlet nutrient signals or predicting the effect of observed terrestrial processes on stream nutrient signals, it is requisite to understand how stream networks can modulate terrestrial nutrient inputs. To date integrated understanding and modeling of physical and biological influences on nutrient concentrations at the stream network scale have been limited. However, watershed scale groundwater ‑ surface water exchange (hydrologic turnover), concentration-variable biological uptake, and the interaction between the two can strongly modify stream water nutrient concentrations. Stream water and associated nutrients are lost to and replaced from groundwater with distinct nutrient concentrations while in-stream nutrients can also be retained by biological processes at rates that vary with concentration. We developed an empirically based network scale model to simulate the interaction between hydrologic turnover and concentration-dependent nutrient uptake across stream networks. Exchange and uptake parameters were measured using conservative and nutrient tracer addition experiments in the Bull Trout Watershed, central Idaho. We found that the interaction of hydrologic turnover and concentration-dependent uptake combined to modify and subsequently stabilize in-stream concentrations, with specific concentrations dependent on the magnitude of hydrologic turnover, groundwater concentrations, and the shape of nutrient uptake kinetic curves. We additionally found that by varying these physical and biological parameters within measured ranges we were able to generate a spectrum of stream network concentration distributions representing a continuum of shifting magnitudes of physical and biological influences on in-stream concentrations. These findings elucidate the important and variable role

  7. Potential pharmacokinetic interactions between antiretrovirals and medicinal plants used as complementary and African traditional medicines.

    Science.gov (United States)

    Müller, Adrienne C; Kanfer, Isadore

    2011-11-01

    The use of traditional/complementary/alternate medicines (TCAMs) in HIV/AIDS patients who reside in Southern Africa is quite common. Those who use TCAMs in addition to antiretroviral (ARV) treatment may be at risk of experiencing clinically significant pharmacokinetic (PK) interactions, particularly between the TCAMs and the protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs). Mechanisms of PK interactions include alterations to the normal functioning of drug efflux transporters, such as P-gp and/or CYP isoenzymes, such a CYP3A4 that mediate the absorption and elimination of drugs in the small intestine and liver. Specific mechanisms include inhibition and activation of these proteins and induction via the pregnane X receptor (PXR). Several clinical studies and case reports involving ARV-herb PK interactions have been reported. St John's Wort, Garlic and Cat's Claw exhibited potentially significant interactions, each with a PI or NNRTI. The potential for these herbs to induce PK interactions with drugs was first identified in reports of in vitro studies. Other in vitro studies have shown that several African traditional medicinal (ATM) plants and extracts may also demonstrate PK interactions with ARVs, through effects on CYP3A4, P-gp and PXR. The most complex effects were exhibited by Hypoxis hemerocallidea, Sutherlandia frutescens, Cyphostemma hildebrandtii, Acacia nilotica, Agauria salicifolia and Elaeodendron buchananii. Despite a high incidence of HIV/AIDs in the African region, only one clinical study, between efavirenz and Hypoxis hemerocallidea has been conducted. However, several issues/concerns still remain to be addressed and thus more studies on ATMs are warranted in order for more meaningful data to be generated and the true potential for such interactions to be determined.

  8. Systems integration of biodefense omics data for analysis of pathogen-host interactions and identification of potential targets.

    Directory of Open Access Journals (Sweden)

    Peter B McGarvey

    Full Text Available The NIAID (National Institute for Allergy and Infectious Diseases Biodefense Proteomics program aims to identify targets for potential vaccines, therapeutics, and diagnostics for agents of concern in bioterrorism, including bacterial, parasitic, and viral pathogens. The program includes seven Proteomics Research Centers, generating diverse types of pathogen-host data, including mass spectrometry, microarray transcriptional profiles, protein interactions, protein structures and biological reagents. The Biodefense Resource Center (www.proteomicsresource.org has developed a bioinformatics framework, employing a protein-centric approach to integrate and support mining and analysis of the large and heterogeneous data. Underlying this approach is a data warehouse with comprehensive protein + gene identifier and name mappings and annotations extracted from over 100 molecular databases. Value-added annotations are provided for key proteins from experimental findings using controlled vocabulary. The availability of pathogen and host omics data in an integrated framework allows global analysis of the data and comparisons across different experiments and organisms, as illustrated in several case studies presented here. (1 The identification of a hypothetical protein with differential gene and protein expressions in two host systems (mouse macrophage and human HeLa cells infected by different bacterial (Bacillus anthracis and Salmonella typhimurium and viral (orthopox pathogens suggesting that this protein can be prioritized for additional analysis and functional characterization. (2 The analysis of a vaccinia-human protein interaction network supplemented with protein accumulation levels led to the identification of human Keratin, type II cytoskeletal 4 protein as a potential therapeutic target. (3 Comparison of complete genomes from pathogenic variants coupled with experimental information on complete proteomes allowed the identification and

  9. Diets of emerald and spottail shiners and potential interactions with other western Lake Erie planktivorous fishes

    Science.gov (United States)

    Hartman, Kyle J.; Vondracek, Bruce; Parrish, Donna L.; Muth, Kenneth M.

    1992-01-01

    Emerald shiner (Notropis atherinoides) and spottail shiner (N. hudsonius) were abundant historically in western Lake Erie. Recent changes in the fish community suggest that shiners may not compete favorably with the invading white perch (Morone americana) or the gizzard shad (Dorosoma cepedianum). We examined the diets of emerald and spottail shiner and compared them to other planktivores in western Lake Erie. Emerald and spottail shiner ate cladocerans such as Daphnia spp.,Leptodora, and Bythotrephes. Biologically significant overlaps (Schoener 1970 index ≥ 0.6) among zooplanktivores occurred from July through September, but most occurred during July. The frequency of significant diet overlaps among planktivores declined since an earlier study in the mid-1970s (Muth and Busch 1989) possibly indicating that competitive interactions have eased since 1975. In addition to competitive interactions, other factors such as increased eutrophication and predator mediated mortality likely played a role in planktivore community changes since the early 1970s.

  10. Assessment of students’ health condition by indicators of adaptation potential, biological age and bio-energetic reserves of organism

    Directory of Open Access Journals (Sweden)

    Martyniuk O.V.

    2015-06-01

    Full Text Available Purpose: to assess students’ health condition by indicators of adaptation potential, biological age and express-assessment. Material: in the research 47 first and second year girl students participated, who belonged to main health group. Results: we distributed the girl students into three groups: 14.89% of them were included in group with “safe” health condition; 34.04% - in group of “third state”; 51.06% were related to group with “ dangerous” health condition. We established that dangerous level was characterized by energy potential of below middle and low level. It is accompanied by accelerated processes of organism’s age destructions and tension of regulation mechanisms. Conclusions: the received results permit to further develop and generalize the data of students’ health’s assessment by indicators of adaptation potentials, biological age and physical health’s condition.

  11. Time evolution of initial states that extend beyond the potential interaction region in quantum decay

    Science.gov (United States)

    García-Calderón, Gastón; Villavicencio, Jorge; Hernández-Maldonado, Alberto; Romo, Roberto

    2016-08-01

    We investigate the decay of initial states that possess a tail that extends beyond the interaction potential region, for potentials of arbitrary shape that vanish exactly after a distance. This is the case for a relevant class of artificial quantum structures. We obtain that along the internal interaction region, the time evolution of the decaying wave function is formed by two terms. The first one refers to the proper decay of the internal portion of the initial state, whereas the second one, that arises from the external tail, yields a transient contribution that tunnels into the internal region, builds up to a value, and then decays. We obtain that depending on the parameters of the initial state, the nonexponential tail decaying contribution may be larger than the contribution of the proper nonexponential term. These results are illustrated by an exactly solvable model and the Heidelberg potential for decay of ultracold atoms and open the possibility to control initial states in artificial decaying systems.

  12. Evaluation of screening length corrections for interaction potentials in impact-collision ion scattering spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Wataru, E-mail: take@sp.ous.ac.jp

    2013-10-15

    Since in impact-collision ion scattering spectroscopy (ICISS) data analysis the interaction potential represented by the screening length as the screening effect is not satisfactorily established up to the present, we introduce commonly the correction factor in the screening length. Previously, Yamamura, Takeuchi and Kawamura (YTK) have suggested the theory taking the shell effect of electron distributions into account for the correction factor to Firsov screening length in the Moliere potential. The application of YTK theory to the evaluation of screening length corrections for the interaction potentials in ICISS manifested that the screening length corrections calculated by the YTK theory agree almost with those determined by simulations or numerical calculations in ICISS and its variants data analyses, being superior to the evaluation of screening length corrections with the O’Connor and Biersack (OB) formula.

  13. Taurolidine Antiadhesive Properties on Interaction with E. coli; Its Transformation in Biological Environment and Interaction with Bacteria Cell Wall

    OpenAIRE

    Caruso, Francesco; James W Darnowski; Opazo, Cristian; Goldberg, Alexander; Kishore, Nina; Agoston, Elin S.; Rossi, Miriam

    2010-01-01

    The taurine amino-acid derivative, taurolidine, bis-(1,1-dioxoperhydro-1,2,4-thiabiazinyl–4)methane, shows broad antibacterial action against gram-positive and gram-negative bacteria, mycobacteria and some clinically relevant fungi. It inhibits, in vitro, the adherence of Escherichia coli and Staphylococcus aureus to human epithelial and fibroblast cells. Taurolidine is unstable in aqueous solution and breaks down into derivatives which are thought to be responsible for the biological activit...

  14. Taurolidine Antiadhesive Properties on Interaction with E. coli; Its Transformation in Biological Environment and Interaction with Bacteria Cell Wall

    OpenAIRE

    Francesco Caruso; Darnowski, James W.; Cristian Opazo; Alexander Goldberg; Nina Kishore; Agoston, Elin S.; Miriam Rossi

    2010-01-01

    The taurine amino-acid derivative, taurolidine, bis-(1,1-dioxoperhydro-1,2,4-thiabiazinyl-4)methane, shows broad antibacterial action against gram-positive and gram-negative bacteria, mycobacteria and some clinically relevant fungi. It inhibits, in vitro, the adherence of Escherichia coli and Staphylococcus aureus to human epithelial and fibroblast cells. Taurolidine is unstable in aqueous solution and breaks down into derivatives which are thought to be responsible for the biological activit...

  15. Exploring potential new floral organ morphogenesis genes of Arabidopsis thaliana using systems biology approach.

    Science.gov (United States)

    Xie, Wenchuan; Huang, Junfeng; Liu, Yang; Rao, Jianan; Luo, Da; He, Miao

    2015-01-01

    Flowering is one of the important defining features of angiosperms. The initiation of flower development and the formation of different floral organs are the results of the interplays among numerous genes. But until now, just fewer genes have been found linked with flower development. And the functions of lots of genes of Arabidopsis thaliana are still unknown. Although, the quartet model successfully simplified the ABCDE model to elaborate the molecular mechanism by introducing protein-protein interactions (PPIs). We still don't know much about several important aspects of flower development. So we need to discriminate even more genes involving in the flower development. In this study, we identified seven differentially modules through integrating the weighted gene co-expression network analysis (WGCNA) and Support Vector Machine (SVM) method to analyze co-expression network and PPIs using the public floral and non-floral expression profiles data of Arabidopsis thaliana. Gene set enrichment analysis was used for the functional annotation of the related genes, and some of the hub genes were identified in each module. The potential floral organ morphogenesis genes of two significant modules were integrated with PPI information in order to detail the inherent regulation mechanisms. Finally, the functions of the floral patterning genes were elucidated by combining the PPI and evolutionary information. It was indicated that the sub-networks or complexes, rather than the genes, were the regulation unit of flower development. We found that the most possible potential new genes underlining the floral pattern formation in A. thaliana were FY, CBL2, ZFN3, and AT1G77370; among them, FY, CBL2 acted as an upstream regulator of AP2; ZFN3 activated the flower primordial determining gene AP1 and AP2 by HY5/HYH gene via photo induction possibly. And AT1G77370 exhibited similar function in floral morphogenesis, same as ELF3. It possibly formed a complex between RFC3 and RPS15 in

  16. Exploring potential new floral organ morphogenesis genes of Arabidopsis thaliana using systems biology approach

    Directory of Open Access Journals (Sweden)

    Wenchuan eXie

    2015-10-01

    Full Text Available Flowering is one of the important defining features of angiosperms. The initiation of flower development and the formation of different floral organs are the results of the interplays among numerous genes. But until now, just fewer genes have been found linked with flower development. And the functions of lots of genes of Arabidopsis thaliana are still unknown. Although, the quartet model successfully simplified the ABCDE model to elaborate the molecular mechanism by introducing protein-protein interactions (PPIs. We still don't know much about several important aspects of flower development. So we need to discriminate even more genes involving in the flower development. In this study, we identified seven differentially modules through integrating the weighted gene co-expression network analysis (WGCNA and Support Vector Machine (SVM method to analyze co-expression network and PPIs using the public floral and non-floral expression profiles data of Arabidopsis thaliana. Gene set enrichment analysis was used for the functional annotation of the related genes, and some of the hub genes were identified in each module. The potential floral organ morphogenesis genes of two significant modules were integrated with PPI information in order to detail the inherent regulation mechanisms. Finally, the functions of the floral patterning genes were elucidated by combining the PPI and evolutionary information. It was indicated that the sub-networks or complexes, rather than the genes, were the regulation unit of flower development. We found that the most possible potential new genes underlining the floral pattern formation in A. thaliana were FY, CBL2, ZFN3 and AT1G77370; among them, FY, CBL2 acted as an upstream regulator of AP2; ZFN3 activated the flower primordial determining gene AP1 and AP2 by HY5/HYH gene via photo induction possibly. And AT1G77370 exhibited similar function in floral morphogenesis, same as ELF3. It possibly formed a complex between RFC3

  17. Fragment Produced by Nuclear Reaction of Heavy Ions Interacted with Tissue-equivalent Biological Material

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In heavy ion therapy and radiation biological effects the nuclear fragments from the heavy ion collisions may cause a significant alteration of the radiation field. Nuclear collision between beam particles and tissue nuclei along the penetration path of high-energy ions in tissue or biological-equivalent material causes a loss

  18. Online Interactive Teaching Modules Enhance Quantitative Proficiency of Introductory Biology Students

    Science.gov (United States)

    Thompson, Katerina V.; Nelson, Karen C.; Marbach-Ad, Gili; Keller, Michael; Fagan, William F.

    2010-01-01

    There is widespread agreement within the scientific and education communities that undergraduate biology curricula fall short in providing students with the quantitative and interdisciplinary problem-solving skills they need to obtain a deep understanding of biological phenomena and be prepared fully to contribute to future scientific inquiry.…

  19. Interactions of nanomaterials with biological systems: A study of bio-mineralized nanoparticles and nanoparticle antibiotics

    Science.gov (United States)

    Gifford, Jennifer Chappell

    Nature is continually able to out-perform laboratory syntheses of nanomaterials with control of specific properties under ambient temperatures, pressures and pH. The investigation of existing biomolecule-mediated nanoparticle synthesis provides insight and knowledge necessary for duplicating these processes. In this way, peptides or proteins with nanomaterial mediation capabilities can be: 1) explored to further understand the ways in which biomolecules create specific nanoparticles then 2) used to create genetically encodable tags for use in electron tomography. The goal of designing such a tag was to assist in closing the resolution gap that exists in current imaging techniques between approximately 5 nm and 100 nm. Presented in this thesis are examples of peptides and proteins that form iron oxide, silver or gold nanoparticles under discrete circumstances. Three iron oxide-related bacterial proteins -- bacterioferritin, Dps and Mms6 -- were investigated for potential use. Similarly, a silver mineralizing peptide, Ge8, was studied upon attachment to the filamentous protein, FtsZ, and a gold mineralizing peptide, A3, was examined to characterize the way in which it mediates the formation of both Au0 nanoclusters and nanoparticles. Given the established interactions that occur between nanoparticles and biomolecules, it may not be surprising that gold nanoparticles displaying specific ratios of functional groups are able to interact with bacteria, in some cases inhibiting growth or causing cell death as antibiotics. A previously developed small molecule variable ligand display (SMVLD) method was expanded to identify a nanoparticle conjugate with a minimal inhibitory concentration (MIC99.9) of 6 muM for Mycobacterium smegmatis, a common laboratory model for M. tuberculosis and the first example of SMVLD applied to mycobacteria. Nanoparticle structure-activity relationships, modes of action and approximations of mammalian cell toxicities were also explored to expand

  20. Preliminary assessment of the interaction of introduced biological agents with biofilms in water distribution systems.

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, Michael B.; Caldwell, Sara; Jones, Howland D. T.; Altman, Susan Jeanne; Souza, Caroline Ann; McGrath, Lucas K.

    2005-12-01

    Basic research is needed to better understand the potential risk of dangerous biological agents that are unintentionally or intentionally introduced into a water distribution system. We report on our capabilities to conduct such studies and our preliminary investigations. In 2004, the Biofilms Laboratory was initiated for the purpose of conducting applied research related to biofilms with a focus on application, application testing and system-scale research. Capabilities within the laboratory are the ability to grow biofilms formed from known bacteria or biofilms from drinking water. Biofilms can be grown quickly in drip-flow reactors or under conditions more analogous to drinking-water distribution systems in annular reactors. Biofilms can be assessed through standard microbiological techniques (i .e, aerobic plate counts) or with various visualization techniques including epifluorescent and confocal laser scanning microscopy and confocal fluorescence hyperspectral imaging with multivariate analysis. We have demonstrated the ability to grow reproducible Pseudomonas fluorescens biofilms in the annular reactor with plate counts on the order of 10{sup 5} and 10{sup 6} CFU/cm{sup 2}. Stationary phase growth is typically reached 5 to 10 days after inoculation. We have also conducted a series of pathogen-introduction experiments, where we have observed that both polystyrene microspheres and Bacillus cereus (as a surrogate for B. anthracis) stay incorporated in the biofilms for the duration of our experiments, which lasted as long as 36 days. These results indicated that biofilms may act as a safe harbor for bio-pathogens in drinking water systems, making it difficult to decontaminate the systems.

  1. Insect antimicrobial peptides show potentiating functional interactions against Gram-negative bacteria

    Science.gov (United States)

    Rahnamaeian, Mohammad; Cytryńska, Małgorzata; Zdybicka-Barabas, Agnieszka; Dobslaff, Kristin; Wiesner, Jochen; Twyman, Richard M.; Zuchner, Thole; Sadd, Ben M.; Regoes, Roland R.; Schmid-Hempel, Paul; Vilcinskas, Andreas

    2015-01-01

    Antimicrobial peptides (AMPs) and proteins are important components of innate immunity against pathogens in insects. The production of AMPs is costly owing to resource-based trade-offs, and strategies maximizing the efficacy of AMPs at low concentrations are therefore likely to be advantageous. Here, we show the potentiating functional interaction of co-occurring insect AMPs (the bumblebee linear peptides hymenoptaecin and abaecin) resulting in more potent antimicrobial effects at low concentrations. Abaecin displayed no detectable activity against Escherichia coli when tested alone at concentrations of up to 200 μM, whereas hymenoptaecin affected bacterial cell growth and viability but only at concentrations greater than 2 μM. In combination, as little as 1.25 μM abaecin enhanced the bactericidal effects of hymenoptaecin. To understand these potentiating functional interactions, we investigated their mechanisms of action using atomic force microscopy and fluorescence resonance energy transfer-based quenching assays. Abaecin was found to reduce the minimal inhibitory concentration of hymenoptaecin and to interact with the bacterial chaperone DnaK (an evolutionarily conserved central organizer of the bacterial chaperone network) when the membrane was compromised by hymenoptaecin. These naturally occurring potentiating interactions suggest that combinations of AMPs could be used therapeutically against Gram-negative bacterial pathogens that have acquired resistance to common antibiotics. PMID:25833860

  2. Insect antimicrobial peptides show potentiating functional interactions against Gram-negative bacteria.

    Science.gov (United States)

    Rahnamaeian, Mohammad; Cytryńska, Małgorzata; Zdybicka-Barabas, Agnieszka; Dobslaff, Kristin; Wiesner, Jochen; Twyman, Richard M; Zuchner, Thole; Sadd, Ben M; Regoes, Roland R; Schmid-Hempel, Paul; Vilcinskas, Andreas

    2015-05-01

    Antimicrobial peptides (AMPs) and proteins are important components of innate immunity against pathogens in insects. The production of AMPs is costly owing to resource-based trade-offs, and strategies maximizing the efficacy of AMPs at low concentrations are therefore likely to be advantageous. Here, we show the potentiating functional interaction of co-occurring insect AMPs (the bumblebee linear peptides hymenoptaecin and abaecin) resulting in more potent antimicrobial effects at low concentrations. Abaecin displayed no detectable activity against Escherichia coli when tested alone at concentrations of up to 200 μM, whereas hymenoptaecin affected bacterial cell growth and viability but only at concentrations greater than 2 μM. In combination, as little as 1.25 μM abaecin enhanced the bactericidal effects of hymenoptaecin. To understand these potentiating functional interactions, we investigated their mechanisms of action using atomic force microscopy and fluorescence resonance energy transfer-based quenching assays. Abaecin was found to reduce the minimal inhibitory concentration of hymenoptaecin and to interact with the bacterial chaperone DnaK (an evolutionarily conserved central organizer of the bacterial chaperone network) when the membrane was compromised by hymenoptaecin. These naturally occurring potentiating interactions suggest that combinations of AMPs could be used therapeutically against Gram-negative bacterial pathogens that have acquired resistance to common antibiotics.

  3. Potential drug–drug interactions in Alzheimer patients with behavioral symptoms

    Directory of Open Access Journals (Sweden)

    Pasqualetti G

    2015-09-01

    Full Text Available Giuseppe Pasqualetti, Sara Tognini, Valeria Calsolaro, Antonio Polini, Fabio Monzani Geriatrics Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy Abstract: The use of multi drug regimens among the elderly population has increased tremendously over the last decade although the benefits of medications are always accompanied by potential harm, even when prescribed at recommended doses. The elderly populations are particularly at an increased risk of adverse drug reactions considering comorbidity, poly-therapy, physiological changes affecting the pharmacokinetics and pharmacodynamics of many drugs and, in some cases, poor compliance due to cognitive impairment and/or depression. In this setting, drug–drug interaction may represent a serious and even life-threatening clinical condition. Moreover, the inability to distinguish drug-induced symptoms from a definitive medical diagnosis often results in addition of yet another drug to treat the symptoms, which in turn increases drug–drug interactions. Cognitive enhancers, including acetylcholinesterase inhibitors and memantine, are the most widely prescribed agents for Alzheimer’s disease (AD patients. Behavioral and psychological symptoms of dementia, including psychotic symptoms and behavioral disorders, represent noncognitive disturbances frequently observed in AD patients. Antipsychotic drugs are at high risk of adverse events, even at modest doses, and may interfere with the progression of cognitive impairment and interact with several drugs including anti-arrhythmics and acetylcholinesterase inhibitors. Other medications often used in AD patients are represented by anxiolytic, like benzodiazepine, or antidepressant agents. These agents also might interfere with other concomitant drugs through both pharmacokinetic and pharmacodynamic mechanisms. In this review we focus on the most frequent drug–drug interactions, potentially harmful, in AD patients with

  4. Reconstruction of the Tip-Surface Interaction Potential by Analysis of the Brownian Motion of an Atomic Force Microscope Tip

    NARCIS (Netherlands)

    Willemsen, Oscar H.; Kuipers, Laurens; Werf, van der Kees O.; Grooth, de Bart G.; Greve, Jan

    2000-01-01

    The thermal movement of an atomic force microscope (AFM) tip is used to reconstruct the tip-surface interaction potential. If a tip is brought into the vicinity of a surface, its movement is governed by the sum of the harmonic cantilever potential and the tip-surface interaction potential. By simula

  5. Association of COMT and COMT-DRD2 interaction with creative potential

    Directory of Open Access Journals (Sweden)

    Shun eZhang

    2014-04-01

    Full Text Available Several lines of evidence suggest that genes involved in dopamine (DA transmission may contribute to creativity. Among these genes, the catechol-O-methyltransferase gene (COMT and the dopamine D2 receptor gene (DRD2 are the most promising candidates. Our previous study has revealed evidence for the involvement of DRD2 in creative potential. The present study extended our previous study by systematically exploring the association of COMT with creative potential as well as the interaction between COMT and DRD2. Twelve single nucleotide polymorphisms (SNPs covering COMT were genotyped in 543 healthy Chinese college students whose creative potentials were assessed by divergent thinking tests. Single SNP analysis showed that rs174697 was nominally associated with verbal originality, two SNPs (rs737865 and rs5993883 were nominally associated with figural fluency, and two SNPs (rs737865 and rs4680 were nominally associated with figural originality. Haplotype analysis showed that, the TCT and CCT haplotype (rs737865-rs174675-rs5993882 were nominally associated with figural originality, and the TATGCAG and CGCGGGA haplotype (rs4646312-rs6269-rs4633-rs6267-rs4818-rs4680-rs769224 were nominally associated with figural originality and verbal flexibility, respectively. However, none of these nominal findings survived correction for multiple testing. Gene-gene interaction analysis identified one significant four-way interaction of rs174675 (COMT, rs174697 (COMT, rs1076560 (DRD2 and rs4436578 (DRD2 on verbal fluency, one significant four-way interaction of rs174675 (COMT, rs4818 (COMT, rs1076560 (DRD2 and rs4648317 (DRD2 on verbal flexibility, and one significant three-way interaction of rs5993883 (COMT, rs4648319 (DRD2 and rs4648317 (DRD2 on figural flexibility. In conclusion, the present study provides nominal evidence for the involvement of COMT in creative potential and suggests that DA related genes may act in coordination to contribute to creativity.

  6. A Study on Potential of Integrating Multimodal Interaction into Musical Conducting Education

    CERN Document Server

    Siang, Gilbert Phuah Leong; Yong, Pang Yee

    2010-01-01

    With the rapid development of computer technology, computer music has begun to appear in the laboratory. Many potential utility of computer music is gradually increasing. The purpose of this paper is attempted to analyze the possibility of integrating multimodal interaction such as vision-based hand gesture and speech interaction into musical conducting education. To achieve this purpose, this paper is focus on discuss some related research and the traditional musical conducting education. To do so, six musical conductors had been interviewed to share their musical conducting learning/ teaching experience. These interviews had been analyzed in this paper to show the syllabus and the focus of musical conducting education for beginners.

  7. Assessing the Soil Physiological Potential Using Pedo-Biological Diagnosis Under Minimum-Tillage System and Mineral Fertilization

    Directory of Open Access Journals (Sweden)

    Lazar Bireescu

    2014-11-01

    Full Text Available The main objective of sustainable agriculture is the protection of environment and natural vegetal and soil resources. Accordingly, the objective of this research was to assess the impact of technological systems by minimum tillage on soil biological activity, using the Pedo-Biological Diagnosis of Soil Resources. Our research was conducted on haplic chernozem from Experimental Station of UASVM of Iasi, Romania, during the seasonal dynamic, to the soybean crop, on unfertilized and fertilized agrofond, using moderate mineral doses (N80P80 as average of 2009–2010 period, under minimum tillage (2x disk, paraplow, chisel compared to conventional (plugging at 20 cm and 30 cm. In the case of soil works with chisel and paraplow without return of furrow, the Pedo-Biological Diagnosis highlights an increase of soil physiological potential, in the both variants (unfertilized and fertilized, unlike the method of alternating the depth of plugging that proved to be ineffective.

  8. Assessment of potential drug-drug interactions and its associated factors in the hospitalized cardiac patients.

    Science.gov (United States)

    Murtaza, Ghulam; Khan, Muhammad Yasir Ghani; Azhar, Saira; Khan, Shujaat Ali; Khan, Tahir M

    2016-03-01

    Drug-drug interactions (DDIs) may result in the alteration of therapeutic response. Sometimes they may increase the untoward effects of many drugs. Hospitalized cardiac patients need more attention regarding drug-drug interactions due to complexity of their disease and therapeutic regimen. This research was performed to find out types, prevalence and association between various predictors of potential drug-drug interactions (pDDIs) in the Department of Cardiology and to report common interactions. This study was performed in the hospitalized cardiac patients at Ayub Teaching Hospital, Abbottabad, Pakistan. Patient charts of 2342 patients were assessed for pDDIs using Micromedex® Drug Information. Logistic regression was applied to find predictors of pDDIs. The main outcome measure in the study was the association of the potential drug-drug interactions with various factors such as age, gender, polypharmacy, and hospital stay of the patients. We identified 53 interacting-combinations that were present in total 5109 pDDIs with median number of 02 pDDIs per patient. Overall, 91.6% patients had at least one pDDI; 86.3% were having at least one major pDDI, and 84.5% patients had at least one moderate pDDI. Among 5109 identified pDDIs, most were of moderate (55%) or major severity (45%); established (24.2%), theoretical (18.8%) or probable (57%) type of scientific evidence. Top 10 common pDDIs included 3 major and 7 moderate interactions. Results obtained by multivariate logistic regression revealed a significant association of the occurrence of pDDIs in patient with age of 60 years or more (p Older patients, patients with longer hospital stay and with elevated number of prescribed drugs were at higher risk of pDDIs. PMID:27013915

  9. Charged patchy particle models in explicit salt: Ion distributions, electrostatic potentials, and effective interactions

    Energy Technology Data Exchange (ETDEWEB)

    Yigit, Cemil; Dzubiella, Joachim, E-mail: joachim.dzubiella@helmholtz-berlin.de [Soft Matter and Functional Materials, Helmholtz-Zentrum Berlin, 14109 Berlin (Germany); Helmholtz Virtual Institute “Multifunctional Biomaterials for Medicine,” 14513 Teltow (Germany); Institut für Physik, Humboldt-Universität zu Berlin, 12489 Berlin (Germany); Heyda, Jan [Department of Physical Chemistry, University of Chemistry and Technology, Prague, 166 28 Praha 6 (Czech Republic)

    2015-08-14

    We introduce a set of charged patchy particle models (CPPMs) in order to systematically study the influence of electrostatic charge patchiness and multipolarity on macromolecular interactions by means of implicit-solvent, explicit-ion Langevin dynamics simulations employing the Gromacs software. We consider well-defined zero-, one-, and two-patched spherical globules each of the same net charge and (nanometer) size which are composed of discrete atoms. The studied mono- and multipole moments of the CPPMs are comparable to those of globular proteins with similar size. We first characterize ion distributions and electrostatic potentials around a single CPPM. Although angle-resolved radial distribution functions reveal the expected local accumulation and depletion of counter- and co-ions around the patches, respectively, the orientation-averaged electrostatic potential shows only a small variation among the various CPPMs due to space charge cancellations. Furthermore, we study the orientation-averaged potential of mean force (PMF), the number of accumulated ions on the patches, as well as the CPPM orientations along the center-to-center distance of a pair of CPPMs. We compare the PMFs to the classical Derjaguin-Verwey-Landau-Overbeek theory and previously introduced orientation-averaged Debye-Hückel pair potentials including dipolar interactions. Our simulations confirm the adequacy of the theories in their respective regimes of validity, while low salt concentrations and large multipolar interactions remain a challenge for tractable theoretical descriptions.

  10. The potential of plants as a system for the development and production of human biologics [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Qiang Chen

    2016-05-01

    Full Text Available The growing promise of plant-made biologics is highlighted by the success story of ZMapp™ as a potentially life-saving drug during the Ebola outbreak of 2014-2016. Current plant expression platforms offer features beyond the traditional advantages of low cost, high scalability, increased safety, and eukaryotic protein modification. Novel transient expression vectors have been developed that allow the production of vaccines and therapeutics at unprecedented speed to control potential pandemics or bioterrorism attacks. Plant-host engineering provides a method for producing proteins with unique and uniform mammalian post-translational modifications, providing opportunities to develop biologics with increased efficacy relative to their mammalian cell-produced counterparts. Recent demonstrations that plant-made proteins can function as biocontrol agents of foodborne pathogens further exemplify the potential utility of plant-based protein production. However, resolving the technical and regulatory challenges of commercial-scale production, garnering acceptance from large pharmaceutical companies, and obtaining U.S. Food and Drug Administration approval for several major classes of biologics are essential steps to fulfilling the untapped potential of this technology.

  11. Medicinal plant reported with adverse reactions in Cuba: potential interactions with conventional drugs

    Directory of Open Access Journals (Sweden)

    Ioanna Martínez

    2015-04-01

    Full Text Available Context: Herbal drugs are a mixture of active compounds and the chemical complexity of each formulation increase with the possibility of interactions between them and conventional drugs. Many mechanisms are implicated in the interactions; scientific community has dedicated the attentions to enzymes as P-gp and CYP450. Aims: To investigate in the literature the principal plants with suspicions of adverse reactions in Cuba and their potential interactions with conventional drugs. Methods: PubMed was the database used as source of information until February 2014. Key words: Herb-Drug, Drug-Plant, Herbal–Drug, Interactions with scientific names of plants was used. Information was structured and analysed with EndNote X4. Analysis and integration of the information: Allium sativum L. (garlic was the plant with the high number of studies related with CYP450 and P-gp. Plants with great demand as Morinda citrifolia L. (noni, Psidium guajava L. (guayaba, Zingiber officinale Roscoe (ginger and Eucalyptus spp. (eucalyptus have a very small number of studies. The professionals of the health should keep in mind the possibility of interactions between herbal products and conventional drugs to increase the effectiveness of phytotherapy. Conclusions: It is necessary enhance reports and investigations and to put to disposition of the system of health information on the interactions of plants and to stimulate the investigation that offers information for the rational use of our medicinal plants.

  12. Mesoscopic biology

    Indian Academy of Sciences (India)

    G V Shivashankar

    2002-02-01

    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 systems. In recent years advances in technology have led to the study of some of the design principles of these machines; in particular at the level of an individual molecule. For example, the forces that operate in molecular interactions, the stochasticity involved in these interactions and their spatio-temporal dynamics are beginning to be explored. Understanding such design principles is opening new possibilities in mesoscopic physics with potential applications.

  13. Electrostatic potential profile and nonlinear current in an interacting one-dimensional molecular wire

    Indian Academy of Sciences (India)

    S Lakshmi; Swapan K Pati

    2003-10-01

    We consider an interacting one-dimensional molecular wire attached to two metal electrodes on either side of it. The electrostatic potential profile across the wire-electrode interface has been deduced solving the Schrodinger and Poisson equations self-consistently. Since the Poisson distribution crucially depends on charge densities, we have considered different Hamiltonian parameters to model the nanoscale wire. We find that for very weak electron correlations, the potential gradient is almost zero in the middle of the wire but are large near the chain ends. However, for strong correlations, the potential is essentially a ramp function. The nonlinear current, obtained from the scattering formalism, is found to be less with the ramp potential than for weak correlations. Some of the interesting features in current-voltage characteristics have been explained using one-electron formalism and instabilities in the system.

  14. Hyperon Single-Particle Potentials Calculated from SU6 Quark-Model Baryon-Baryon Interactions

    CERN Document Server

    Kohno, M; Fujita, T; Nakamoto, C; Suzuki, Y

    2000-01-01

    Using the SU6 quark-model baryon-baryon interaction recently developed by the Kyoto-Niigata group, we calculate NN, Lambda N and Sigma N G-matrices in ordinary nuclear matter. This is the first attempt to discuss the Lambda and Sigma single-particle potentials in nuclear medium, based on the realistic quark-model potential. The Lambda potential has the depth of more than 40 MeV, which is more attractive than the value expected from the experimental data of Lambda-hypernuclei. The Sigma potential turns out to be repulsive, the origin of which is traced back to the strong Pauli repulsion in the Sigma N (I=3/2) ^3S_1 state.

  15. Biological response modifiers and their potential use in the treatment of inflammatory skin diseases

    DEFF Research Database (Denmark)

    Villadsen, Louise S; Skov, Lone; Baadsgaard, Ole

    2003-01-01

    and fewer side-effects than the current systemic therapies now used for severe psoriasis, contact dermatitis and atopic dermatitis. In the pathogenesis of inflammatory skin diseases, the immune system plays a pivotal role, and this is where biological response modifiers such as monoclonal antibodies...

  16. Does phylogeny explain the host choice behaviour of potential biological control agents for Brassicaceae weeds?

    Science.gov (United States)

    Four invasive Brassicaceae are currently being studied for biological control at the CABI Centre in Switzerland. A phylogenetic approach to host testing has so far been hampered by the fact that the evolutionary relationships of taxa within the Brassicaceae were unclear. Recently, a new phylogeny of...

  17. Exploring the potential of second-generation sequencing in diverse biological contexts

    DEFF Research Database (Denmark)

    Fordyce, Sarah Louise

    H1N1 influenza A virus genomes. The results of these studies demonstrate the power of SGS for gaining insight into the genetic variation of diverse biological samples and highlight the importance of using optimized protocols for sequencing non-conventional samples....

  18. Gene Network Biological Validity Based on Gene-Gene Interaction Relevance

    OpenAIRE

    Francisco Gómez-Vela; Norberto Díaz-Díaz

    2014-01-01

    In recent years, gene networks have become one of the most useful tools for modeling biological processes. Many inference gene network algorithms have been developed as techniques for extracting knowledge from gene expression data. Ensuring the reliability of the inferred gene relationships is a crucial task in any study in order to prove that the algorithms used are precise. Usually, this validation process can be carried out using prior biological knowledge. The metabolic pathways stored in...

  19. Development of a General Modeling Framework for Investigating Complex Interactions among Biological and Physical Ecosystem Dynamics

    Science.gov (United States)

    Bennett, C.; Poole, G. C.; Kimball, J. S.; Stanford, J. A.; O'Daniel, S. J.; Mertes, L. A.

    2005-05-01

    Historically, physical scientists have developed models with highly accurate governing equations, while biologists have excelled at abstraction (the strategic simplification of system complexity). These different modeling paradigms yield biological (e.g. food web) and physical (e.g. hydrologic) models that can be difficult to integrate. Complex biological dynamics may be impossible to represent with governing equations. Conversely, physical processes may be oversimplified in biological models. Using agent-based modeling, a technique applied widely in social sciences and economics, we are developing a general modeling system to integrate accurate representations of physical dynamics such as water and heat flux with abstracted biological processes such as nutrient transformations. The modeling system represents an ecosystem as a complex integrated network of intelligent physical and biological "agents" that store, transform, and trade ecosystem resources (e.g., water, heat, nutrients, carbon) using equations that describe either abstracted concepts and/or physical laws. The modular design of the system allows resource submodels to be developed independently and installed into the simulation architecture. The modeling system provides a useful heuristic tool to support integrated physical and biological research topics, such as the influence of hydrologic dynamics and spatio-temporal physical heterogeneity on trophic (food web) dynamics and/or nutrient cycling.

  20. The interaction potential of NO-H2 in ground and A Rydberg state

    Science.gov (United States)

    Pajón-Suárez, Pedro; Valentín-Rodríguez, Mónica; Hernández-Lamoneda, Ramón

    2016-08-01

    The interaction potential for the ground and A Rydberg state of NO-H2 has been calculated using high level ab initio methods. The complex is very floppy in nature and large amplitude motions are expected to characterize its dynamics. The ground state is characterized by two very close-lying states which exhibit crossings. By analogy with other complexes the Rydberg state is characterized by much smaller well depth and larger intermolecular distance. We compare with model potentials used in previous molecular dynamics simulations of photoexcitation and relaxation and conclude on the importance of performing new studies.

  1. The potential of protein-nanomaterial interaction for advanced drug delivery

    DEFF Research Database (Denmark)

    Peng, Qiang; Mu, Huiling

    2016-01-01

    Nanomaterials, like nanoparticles, micelles, nano-sheets, nanotubes and quantum dots, have great potentials in biomedical fields. However, their delivery is highly limited by the formation of protein corona upon interaction with endogenous proteins. This new identity, instead of nanomaterial itself......, would be the real substance the organs and cells firstly encounter. Consequently, the behavior of nanomaterials in vivo is uncontrollable and some undesired effects may occur, like rapid clearance from blood stream; risk of capillary blockage; loss of targeting capacity; and potential toxicity...

  2. Potential of lateral interactions of CO on Pt (111) fitted to recent STM images

    Science.gov (United States)

    Myshlyavtsev, Alexander V.; Stishenko, Pavel V.

    2015-12-01

    Monolayers of carbon monoxide (CO) on Pt(111) surfaces are one of the most studied adsorption systems. However, molecular models of this system still do not take into account the reliable potential of lateral interactions between adsorbed CO molecules. Recent advances in experimental technique have brought high-resolution real-space images of CO/Pt(111) monolayers. For example, Yang et al. (J. Phys. Chem. C 117 (2013) 16429-16437) found island structures for coverages from 0.11 to 0.25 ML. In this study we have shown that these island structures can be explained with long-range oscillating lateral interactions. Parameters of the proposed potential were fitted to experimental scanning tunneling microscopy images with a series of Monte Carlo simulations.

  3. Multireference configuration interaction calculations of the first six ionization potentials of the uranium atom

    Energy Technology Data Exchange (ETDEWEB)

    Bross, David H.; Parmar, Payal; Peterson, Kirk A., E-mail: kipeters@wsu.edu [Department of Chemistry, Washington State University, Pullman, Washington 99164-4630 (United States)

    2015-11-14

    The first 6 ionization potentials (IPs) of the uranium atom have been calculated using multireference configuration interaction (MRCI+Q) with extrapolations to the complete basis set limit using new all-electron correlation consistent basis sets. The latter was carried out with the third-order Douglas-Kroll-Hess Hamiltonian. Correlation down through the 5s5p5d electrons has been taken into account, as well as contributions to the IPs due to the Lamb shift. Spin-orbit coupling contributions calculated at the 4-component Kramers restricted configuration interaction level, as well as the Gaunt term computed at the Dirac-Hartree-Fock level, were added to the best scalar relativistic results. The final ionization potentials are expected to be accurate to at least 5 kcal/mol (0.2 eV) and thus more reliable than the current experimental values of IP{sub 3} through IP{sub 6}.

  4. Isospin effects of the Skyrme potential and the momentum dependent interaction at intermediate energy heavy ion collisions

    Institute of Scientific and Technical Information of China (English)

    GUO Wen-Jun; LIU Jian-Ye

    2008-01-01

    We improve the isospin dependent quantum molecular dynamical model by including isospin effects in the Skyrme potential and the momentum dependent interaction to obtain an isospin dependent Skyrme potential and an isospin dependent momentum interaction. We investigate the isospin effects of Skyrme potential and momentum dependent interaction on the isospin fractionation ratio and the dynamical mechanism in intermediate energy heavy ion collisions. It is found that the isospin dependent Skyrme potential and the isospin dependent momentum interaction produce some important isospin effects in the isospin fractionation ratio.

  5. Herbal medicines in Brazil: pharmacokinetic profile and potential herb-drug interactions.

    Science.gov (United States)

    Mazzari, Andre L D A; Prieto, Jose M

    2014-01-01

    A plethora of active compounds found in herbal medicines can serve as substrate for enzymes involved in the metabolism of xenobiotics. When a medicinal plant is co-administered with a conventional drug and little or no information is known about the pharmacokinetics of the plant metabolites, there is an increased risk of potential herb-drug interactions. Moreover, genetic polymorphisms in a population may act to predispose individuals to adverse reactions. The use of herbal medicines is rapidly increasing in many countries, particularly Brazil where the vast biodiversity is a potential source of new and more affordable treatments for numerous conditions. Accordingly, the Brazilian Unified Public Health System (SUS) produced a list of 71 plant species of interest, which could be made available to the population in the near future. Physicians at SUS prescribe a number of essential drugs and should herbal medicines be added to this system the chance of herb-drug interactions further increases. A review of the effects of these medicinal plants on Phase 1 and Phase 2 metabolic mechanisms and the transporter P-glycoprotein was conducted. The results have shown that approximately half of these medicinal plants lack any pharmacokinetic data. Moreover, most of the studies carried out are in vitro. Only a few reports on herb-drug interactions with essential drugs prescribed by SUS were found, suggesting that very little attention is being given to the safety of herbal medicines. Here we have taken this information to discuss the potential interactions between herbal medicines and essential drugs prescribed to Brazilian patients whilst taking into account the most common polymorphisms present in the Brazilian population. A number of theoretical interactions are pinpointed but more pharmacokinetic studies and pharmacovigilance data are needed to ascertain their clinical significance.

  6. Mach-Zehnder interferometry with interacting Bose-Einstein condensates in a double-well potential

    International Nuclear Information System (INIS)

    Mach-Zehnder interferometry with interacting Bose-Einstein condensates in a double-well potential Particle-wave duality has enabled the construction of interferometers for massive particles such as electrons, neutrons, atoms or molecules. Implementing atom interferometry has required the development of analogues to the optical beam-splitters, phase shifters or recombiners to enable the coherent, i.e. phase-preserving manipulation of quantum superpositions. While initially demonstrating the wave nature of particles, atom interferometers have evolved into some of the most advanced devices for precision measurement, both for technological applications and tests of the fundamental laws of nature. Bose- Einstein condensates (BEC) of ultracold atoms are particular matter waves: they exhibit a collective many-body wave function and macroscopic coherence properties. As such, they have often been considered as an analogue to optical laser elds and it is natural to wonder whether BECs can provide to atom interferometry a similar boost as the laser brought to optical interferometry. One fundamental dierence between atomic BECs and lasers elds is the presence of atomic interactions, yielding an intrinsic non-linearity. On one hand, interactions can lead to eects destroying the phase coherence and limiting the interrogation time of trapped BEC interferometers. On the other hand, they can be used to generate nonclassical (e.g. squeezed) states to improve the sensitivity of interferometric measurements beyond the standard quantum limit (SQL). In this thesis, we present the realization of a full Mach-Zehnder interferometric sequence with trapped, interacting BECs con ned on an atom chip. Our interferometer relies on the coherent manipulation of a BEC in a magnetic double-well potential. For this purpose, we developed a novel type of matter-wave recombiner, an element which so far was missing in BEC atom optics. We have been able to exploit interactions to generate a squeezed

  7. The potential of text mining in data integration and network biology for plant research: a case study on Arabidopsis

    OpenAIRE

    Van Landeghem, Sofie; De Bodt, Stefanie; Drebert, Zuzanna; Inzé, Dirk; Van de Peer, Yves

    2013-01-01

    Despite the availability of various data repositories for plant research, a wealth of information currently remains hidden within the biomolecular literature. Text mining provides the necessary means to retrieve these data through automated processing of texts. However, only recently has advanced text mining methodology been implemented with sufficient computational power to process texts at a large scale. In this study, we assess the potential of large-scale text mining for plant biology res...

  8. A systems biology approach to identify intelligence quotient score-related genomic regions, and pathways relevant to potential therapeutic treatments

    OpenAIRE

    Min Zhao; Lei Kong; Hong Qu

    2014-01-01

    Although the intelligence quotient (IQ) is the most popular intelligence test in the world, little is known about the underlying biological mechanisms that lead to the differences in human. To improve our understanding of cognitive processes and identify potential biomarkers, we conducted a comprehensive investigation of 158 IQ-related genes selected from the literature. A genomic distribution analysis demonstrated that IQ-related genes were enriched in seven regions of chromosome 7 and the X...

  9. Floral biology of the Cunoniaceae in New Caledonia and the role of insects, birds and geckos as potential pollinators

    OpenAIRE

    Hopkins, H.C.F.; Bradford, J.C.; Donovan, B; Pillon, Y.; Munzinger, Jérôme; Fogliani, B.

    2015-01-01

    Cunoniaceae are represented in New Caledonia by some 90 species, all of them endemic, and the family is thus a significant element in this diverse island flora. We present a descriptive survey of floral biology for the seven genera present, covering floral structure and colour, inflorescence shape, sexual system and phenology, plus details of floral visitors, where known, based on field observations; individual records of potential pollinators are tabulated in appendices. The flowers are poly...

  10. SEROTONERGIC/GLUTAMATERGIC INTERACTIONS: POTENTIATION OF PHENCYCLIDINE-INDUCED STIMULUS CONTROL BY CITALOPRAM

    OpenAIRE

    Winter, J. C.; Eckler, J.R.; Rice, K. C.; Rabin, R. A.

    2005-01-01

    Previous investigations in our laboratory have found that the stimulus effects of the hallucinogenic serotonergic agonists DOM and LSD are potentiated by phencyclidine [PCP], a non-competitive NMDA antagonist. Also suggestive of behaviorally significant serotonergic/glutamatergic interactions is our finding that stimulus control by both PCP and LSD is partially antagonized by the mGlu2/3 agonist, LY 379268. These observations coupled with the fact that the stimulus effects of LSD and DOM are ...

  11. Effective interactions for valence-hole nuclei with modern meson-exchange potential models

    International Nuclear Information System (INIS)

    Within the framework of the folded-diagram theory, the authors have studied the effective interaction appropriate for hole-hole nuclei in the mass regions of 16O and 40Ca, using the Bonn and Paris potential models. To sum up the folded diagrams the renormalization procedure of Lee and Suzuki has been employed, using a so-called Q-box in which were included all one-body and two-body irreducible valence-linked diagrams through third order in perturbation theory. Discrepancies for the mass dependence of the effective interaction for several JT configurations with respect to empirically deduced mass dependencies is reported. The role of core polarization processes through third order were found to be one of the mechanisms behind these discrepancies. Compared to the results obtained with the Paris potential, more attraction is introduced by the Bonn potential for all matrix elements of concerns, a result which agrees well with previous findings for the particle-particle interaction in the same mass regions. A qualitative agreements with experimental data is obtained. 31 refs., 6 figs., 8 tabs

  12. Biological interactions of quantum dot nanoparticles in skin and in human epidermal keratinocytes.

    Science.gov (United States)

    Zhang, Leshuai W; Yu, William W; Colvin, Vicki L; Monteiro-Riviere, Nancy A

    2008-04-15

    Quantum dots nanoparticles have novel optical properties for biomedical applications and electronics, but little is known about their skin permeability and interaction with cells. QD621 are nail-shaped nanoparticles that contain a cadmium/selenide core with a cadmium sulfide shell coated with polyethylene glycol (PEG) and are soluble in water. QD were topically applied to porcine skin flow-through diffusion cells to assess penetration at 1 microM, 2 microM and 10 microM for 24 h. QD were also studied in human epidermal keratinocytes (HEK) to determine cellular uptake, cytotoxicity and inflammatory potential. Confocal microscopy depicted the penetration of QD621 through the uppermost stratum corneum (SC) layers of the epidermis and fluorescence was found primarily in the SC and near hair follicles. QD were found in the intercellular lipid bilayers of the SC by transmission electron microscopy (TEM). Inductively coupled plasma-optical emission spectroscopy (ICP-OES) analysis for cadmium (Cd) and fluorescence for QD both did not detect Cd nor fluorescence signal in the perfusate at any time point or concentration. In HEK, viability decreased significantly (p<0.05) from 1.25 nM to 10 nM after 24 h and 48 h. There was a significant increase in IL-6 at 1.25 nM to 10 nM, while IL-8 increased from 2.5 nM to 10 nM after 24 h and 48 h. TEM of HEK treated with 10 nM of QD621 at 24 h depicted QD in cytoplasmic vacuoles and at the periphery of the cell membranes. These results indicate that porcine skin penetration of QD621 is minimal and limited primarily to the outer SC layers, yet if the skin were damaged allowing direct QD exposure to skin or keratinocytes, an inflammatory response could be initiated. PMID:18261754

  13. Biological interactions of quantum dot nanoparticles in skin and in human epidermal keratinocytes

    International Nuclear Information System (INIS)

    Quantum dots nanoparticles have novel optical properties for biomedical applications and electronics, but little is known about their skin permeability and interaction with cells. QD621 are nail-shaped nanoparticles that contain a cadmium/selenide core with a cadmium sulfide shell coated with polyethylene glycol (PEG) and are soluble in water. QD were topically applied to porcine skin flow-through diffusion cells to assess penetration at 1 μM, 2 μM and 10 μM for 24 h. QD were also studied in human epidermal keratinocytes (HEK) to determine cellular uptake, cytotoxicity and inflammatory potential. Confocal microscopy depicted the penetration of QD621 through the uppermost stratum corneum (SC) layers of the epidermis and fluorescence was found primarily in the SC and near hair follicles. QD were found in the intercellular lipid bilayers of the SC by transmission electron microscopy (TEM). Inductively coupled plasma-optical emission spectroscopy (ICP-OES) analysis for cadmium (Cd) and fluorescence for QD both did not detect Cd nor fluorescence signal in the perfusate at any time point or concentration. In HEK, viability decreased significantly (p < 0.05) from 1.25 nM to 10nM after 24 h and 48 h. There was a significant increase in IL-6 at 1.25 nM to 10 nM, while IL-8 increased from 2.5nM to 10nM after 24 h and 48 h. TEM of HEK treated with 10 nM of QD621 at 24 h depicted QD in cytoplasmic vacuoles and at the periphery of the cell membranes. These results indicate that porcine skin penetration of QD621 is minimal and limited primarily to the outer SC layers, yet if the skin were damaged allowing direct QD exposure to skin or keratinocytes, an inflammatory response could be initiated

  14. Potential of the PIGE method in the analysis of biological and mineral materials

    International Nuclear Information System (INIS)

    A possible application of the PIGE method for the analysis of the biological and mineral samples has been tested using a 3.5 MeV Van de Graaff accelerator. The limits of detection of 4 mg/kg for fluorine, 10 mg/kg for aluminium and 200 mg/kg for phosphorus were achieved with a 3.15 MeV proton beam (8 mm in diameter, 20 nA current and 1000 s irradiation time). The PIGE method was found to be a suitable method for the determination of fluorine in the samples analyzed. With this technique, total fluorine in the sample can be quantitated without any chemical treatment. In the analysis of the phosphorus in thick biological samples, PIGE can compete with PIXE and is probably less sensitive to matrix effects and spectra fitting, which may bring about a higher accuracy of the results

  15. Mechanical–biological treatment: Performance and potentials. An LCA of 8 MBT plants including waste characterization

    DEFF Research Database (Denmark)

    Montejo, Cristina; Tonini, Davide; Márquez, María del Carmen;

    2013-01-01

    In the endeavour of avoiding presence of biodegradable waste in landfills and increasing recycling, mechanical–biological treatment (MBT) plants have seen a significant increase in number and capacity in the last two decades. The aim of these plants is separating and stabilizing the quickly...... biodegradable fraction of the waste as well as recovering recyclables from mixed waste streams. In this study the environmental performance of eight MBT-based waste management scenarios in Spain was assessed by means of life cycle assessment. The focus was on the technical and environmental performance...... of the MBT plants. These widely differed in type of biological treatment and recovery efficiencies. The results indicated that the performance is strongly connected with energy and materials recovery efficiency. The recommendation for upgrading and/or commissioning of future plants is to optimize materials...

  16. Developmental changes in sleep biology and potential effects on adolescent behavior and caffeine use

    OpenAIRE

    Carskadon, Mary A.; Tarokh, Leila

    2014-01-01

    Adolescent development includes changes in the biological regulatory processes for the timing of sleep. Circadian rhythm changes and changes to the sleep-pressure system (sleep homeostasis) during adolescence both favor later timing of sleep. These changes, combined with prevailing social pressures, are responsible for most teens sleeping too late and too little; those who sleep least report consuming more caffeine. Although direct research findings are scarce, the likelihood of use and abuse...

  17. The Thymus–Neuroendocrine Axis: Physiology, Molecular Biology, and Therapeutic Potential of the Thymic Peptide Thymulin

    OpenAIRE

    Reggiani, Paula C.; Morel, Gustavo R.; Cónsole, Gloria M.; Barbeito, Claudio G; Rodriguez, Silvia S.; Brown, Oscar A.; Bellini, Maria Jose; Pléau, Jean-Marie; Dardenne, Mireille; Goya, Rodolfo G.

    2009-01-01

    Thymulin is a thymic hormone exclusively produced by the thymic epithelial cells. It consists of a nonapeptide component coupled to the ion zinc, which confers biological activity to the molecule. After its discovery in the early 1970s, thymulin was characterized as a thymic hormone involved in several aspects of intrathymic and extrathymic T cell differentiation. Subsequently, it was demonstrated that thymulin production and secretion is strongly influenced by the neuroendocrine system. Conv...

  18. Using a biological indicator to detect potential sources of cross-contamination in the dental operatory.

    Science.gov (United States)

    Hackney, R W; Crawford, J J; Tulis, J J

    1998-11-01

    The authors conducted a study using surveillance monitoring methodology to identify operatory contamination and to evaluate the effectiveness of infection control procedures. Viridans streptococci were evaluated as biological indicators of oral contamination. Viridans streptococci, abundant in human saliva, were detected on operatory surfaces after dental treatments were finished and surfaces were disinfected. The findings validate current concepts of infection control as demonstrated in barrier methods.

  19. Potential impact of subsequent entry biologics in nephrology practice in Canada

    OpenAIRE

    Martinusen, Daniel J; Lo, Clifford; Marin, Judith G; Tsao, Nicole W.; Leung, Marianna

    2014-01-01

    Purpose of review Subsequent entry biologics may soon be a reality in Canadian nephrology practice. Along with opportunities to reduce health care costs, these agents pose unique challenges that must be met for successful implementation. Understanding the experiences around the globe in both regulatory affairs and implementation will be a valuable guide for Canadian clinicians. This report provides an executive summary of the information required to guide decisions to use or implement subsequ...

  20. Improving intermolecular interactions in DFTB3 using extended polarization from chemical-potential equalization

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, Anders S., E-mail: andersx@chem.wisc.edu, E-mail: cui@chem.wisc.edu; Cui, Qiang, E-mail: andersx@chem.wisc.edu, E-mail: cui@chem.wisc.edu [Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706 (United States); Elstner, Marcus [Theoretische Chemische Biologie, Universität Karlsruhe, Kaiserstr. 12, 76131 Karlsruhe (Germany)

    2015-08-28

    Semi-empirical quantum mechanical methods traditionally expand the electron density in a minimal, valence-only electron basis set. The minimal-basis approximation causes molecular polarization to be underestimated, and hence intermolecular interaction energies are also underestimated, especially for intermolecular interactions involving charged species. In this work, the third-order self-consistent charge density functional tight-binding method (DFTB3) is augmented with an auxiliary response density using the chemical-potential equalization (CPE) method and an empirical dispersion correction (D3). The parameters in the CPE and D3 models are fitted to high-level CCSD(T) reference interaction energies for a broad range of chemical species, as well as dipole moments calculated at the DFT level; the impact of including polarizabilities of molecules in the parameterization is also considered. Parameters for the elements H, C, N, O, and S are presented. The Root Mean Square Deviation (RMSD) interaction energy is improved from 6.07 kcal/mol to 1.49 kcal/mol for interactions with one charged species, whereas the RMSD is improved from 5.60 kcal/mol to 1.73 for a set of 9 salt bridges, compared to uncorrected DFTB3. For large water clusters and complexes that are dominated by dispersion interactions, the already satisfactory performance of the DFTB3-D3 model is retained; polarizabilities of neutral molecules are also notably improved. Overall, the CPE extension of DFTB3-D3 provides a more balanced description of different types of non-covalent interactions than Neglect of Diatomic Differential Overlap type of semi-empirical methods (e.g., PM6-D3H4) and PBE-D3 with modest basis sets.

  1. First Evaluation of the Biologically Active Substances and Antioxidant Potential of Regrowth Velvet Antler by means of Multiple Biochemical Assays

    Directory of Open Access Journals (Sweden)

    Yujiao Tang

    2015-01-01

    Full Text Available We investigated the biologically active substances contained in RVA (regrowth velvet antler by comparing the composition of biologically active substances and antioxidant potential of different antler segments. RVA was subjected to extraction using DW (distilled water. RVA was divided into 3 segments: T-RVA (top RVA, M-RVA (middle RVA, and B-RVA (base RVA. The T-RVA section possessed the greatest amounts of uronic acid (36.251 mg/g, sulfated GAGs (sulfated glycosaminoglycans (555.76 mg/g, sialic acid (111.276 mg/g, uridine (0.957 mg/g, uracil (1.084 mg/g, and hypoxanthine (1.2631 mg/g. In addition, the T-RVA section possessed the strongest antioxidant capacity as determined by DPPH, H2O2 (hydrogen peroxide, hydroxyl, and ABTS (2,2′-azinobis-3-ethylbenzthiazoline-6-sulphonate radical scavenging activity as well as FRAP (ferric reducing antioxidant power and ORAC (oxygen radical absorbance capacity. The values of those were 53.44, 23.09, 34.12, 60.31, and 35.81 TE/μM at 1 mg/mL and 113.57 TE/μM at 20 μg/mL. These results indicate that the T-RVA section possesses the greatest amount of biologically active substances and highest antioxidant potential. This is the first report on the biologically active substances and antioxidant potential of RVA.

  2. Whitebark pine facilitation at treeline: potential interactions for disruption by an invasive pathogen.

    Science.gov (United States)

    Tomback, Diana F; Blakeslee, Sarah C; Wagner, Aaron C; Wunder, Michael B; Resler, Lynn M; Pyatt, Jill C; Diaz, Soledad

    2016-08-01

    In stressful environments, facilitation often aids plant establishment, but invasive plant pathogens may potentially disrupt these interactions. In many treeline communities in the northern Rocky Mountains of the U.S. and Canada, Pinus albicaulis, a stress-tolerant pine, initiates tree islands at higher frequencies than other conifers - that is, leads to leeward tree establishment more frequently. The facilitation provided by a solitary (isolated) P. albicaulis leading to tree island initiation may be important for different life-history stages for leeward conifers, but it is not known which life-history stages are influenced and protection provided. However, P. albicaulis mortality from the non-native pathogen Cronartium ribicola potentially disrupts these facilitative interactions, reducing tree island initiation. In two Rocky Mountain eastern slope study areas, we experimentally examined fundamental plant-plant interactions which might facilitate tree island formation: the protection offered by P. albicaulis to leeward seed and seedling life-history stages, and to leeward krummholz conifers. In the latter case, we simulated mortality from C. ribicola for windward P. albicaulis to determine whether loss of P. albicaulis from C. ribicola impacts leeward conifers. Relative to other common solitary conifers at treeline, solitary P. albicaulis had higher abundance. More seeds germinated in leeward rock microsites than in conifer or exposed microsites, but the odds of cotyledon seedling survival during the growing season were highest in P. albicaulis microsites. Planted seedling survival was low among all microsites examined. Simulating death of windward P. albicaulis by C. ribicola reduced shoot growth of leeward trees. Loss of P. albicaulis to exotic disease may limit facilitation interactions and conifer community development at treeline and potentially impede upward movement as climate warms. PMID:27551372

  3. Interaction of electromagnetic energy with biological material - relation to food processing

    NARCIS (Netherlands)

    Ponne, C.T.; Bartels, P.V.

    1995-01-01

    For food scientists and technologists, the interaction of electromagnetic energy with enzymes, microorganisms and other food compounds is important in optimizing process efficiency and/or product quality. To be able to implement research findings on interaction of electromagnetic energy with matter;

  4. Dirac equation for the Hulthén potential within the Yukawa-type tensor interaction

    Institute of Scientific and Technical Information of China (English)

    Oktay Aydo(g)du; Elham Maghsoodi; Hassan Hassanabadi

    2013-01-01

    Using the Nikiforov-Uvarov (NU) method,pseudospin and spin symmetric solutions of the Dirac equation for the scalar and vector Hulthén potentials with the Yukawa-type tensor potential are obtained for an arbitrary spin-orbit coupling quantum number κ.We deduce the energy eigenvalue equations and corresponding upper-and lower-spinor wave functions in both the pseudospin and spin symmetry cases.Numerical results of the energy eigenvalue equations and the upper-and lower-spinor wave functions are presented to show the effects of the external potential and particle mass parameters as well as pseudospin and spin symmetric constants on the bound-state energies and wave functions in the absence and presence of the tensor interaction.

  5. A paradigm shift in EPH receptor interaction: biological relevance of EPHB6 interaction with EPHA2 and EPHB2 in breast carcinoma cell lines.

    Science.gov (United States)

    Fox, Brian P; Kandpal, Raj P

    2011-01-01

    EPH receptors are the largest known family of receptor tyrosine kinases characterized in humans. These proteins are involved in axon guidance, tissue organization, synaptic plasticity, vascular development and the progression of various diseases including cancer. The varied biological effects of EPH receptors are mediated in part by the expression of these proteins and their intracellular binding proteins. The ability of EPH molecules to form heterodimers within their own class has been suggested, although not exhaustively characterized. We have clarified this phenomenon by showing that EPHB6, a kinase-deficient receptor, can interact with EPHB2 in mammalian cells, and more significantly EPHB6 interacts with EPHA2. However, EPHB6 does not interact with another kinase-deficient receptor, EPHA10. The interaction between EPHB6 and EPHA2 is the first demonstration of an A-type receptor interacting with a B-type receptor. Furthermore, we correlated relative expression of EPHB6, EPHB2 and EPHA2 with non-invasive and invasive phenotypes of breast tumor cell lines. Our results indicate that tumor invasiveness-suppressing activity of EPHB6 is mediated by its ability to sequester other kinase-sufficient and oncogenic EPH receptors. These observations suggest that cellular phenotypes may, in part, be attributed to a combinatorial expression of EPH receptors and heteromeric interactions among the same class, as well as between two classes, of EPH receptors. Our results also suggest that EPHA10 may transduce signals by interacting with other kinase-sufficient receptors in a similar manner. PMID:21737611

  6. Intermolecular Interaction Potentials of CH4-Ne Complex Calculated with Local Density Approximation Methods

    Institute of Scientific and Technical Information of China (English)

    BAI Yu-Lin; CHENG Xiao-Hong; CHEN Xiang-Rong; YANG Xiang-Dong; ZHU Jun

    2004-01-01

    @@ The intermolecular interactions potentials for two configurations of CH4-Ne complex are calculated with local density approximation methods in the frame of density functional theory. It is found that the calculated potentials have two minima when the distance between the carbon atom of CH4 and the Ne atom takes R = 5.80 a.u.and 6.20a. u. for both the two configurations. For the edge configuration, the corresponding depth of the potential is 0.0669536 eV and 0.0671416 eV. For the face configuration, the corresponding depth of the potential is 0.0737956 eV and 0.0645506 eV. The global minimum occurs at R = 5.80 a.u. for the face configuration with a depth of the potential 0.0737956 eV. The depths of our calculation are in better agreement with the experimental data than the quantum chemical calculation approach, while the position of minimum potential for our calculation is underestimated.

  7. The Potential Role of Nuclear Techniques in Support of the Production of Biological Control Agents of Insect Pests

    International Nuclear Information System (INIS)

    While nuclear techniques could play a vital role in enabling cost-effective mass production of beneficial insects for use in augmentative biological control, surprisingly little use has been made of these techniques or ionizing radiation produced by other means (e.g., x-rays or electron beams from linear accelerators) for mass rearing beneficial insects. This technology has been available for quite some time, having been used to reproductively sterilize screwworm flies as early as 1951 (Bushland and Hopkins). Similarly, gamma radiation has been accepted internationally for human food preservation and disinfestation for many years (Anon., 1995). Quite a number of gamma radiation sources exist at or near USDA ARS and APHIS facilities throughout the U.S., as well as in many universities. Still, relatively little use has been made of this approach to assist in mass rearing of beneficial insects for use in augmentative biological control. As pointed out by Benbrook (1996), pest management is at a crossroads, and there still is a great need for new, biointensive pest management strategies. Nuclear techniques should play an increasing role in the future, as the overall thrust of biological control moves more and more toward augmentative releases (Knipling, 1992). It is the intent of this presentation to review some of the existing and potential uses that can be made of nuclear techniques and other sources of ionizing radiation in support of the biological control of insect pests. (author)

  8. Potential impacts from biological aerosols on ensembles of continental clouds simulated numerically

    Directory of Open Access Journals (Sweden)

    V. T. J. Phillips

    2009-06-01

    Full Text Available An aerosol-cloud modeling framework is described to simulate the activation of ice particles and droplets by biological aerosol particles, such as airborne ice-nucleation active (INA bacteria. It includes the empirical parameterisation of heterogeneous ice nucleation and a semi-prognostic aerosol component, which have been incorporated into a cloud-system resolving model (CSRM with double-moment bulk microphysics. The formation of cloud liquid by soluble material coated on these partially insoluble organic aerosols is represented. It determines their partial removal from deep convective clouds by accretion onto precipitation in the cloud model. This "aerosol-cloud model" is validated for diverse cases of deep convection with contrasting aerosol conditions, against satellite, ground-based and aircraft observations.

    Simulations are performed with the aerosol-cloud model for a month-long period of summertime convective activity over Oklahoma. It includes three cases of continental deep convection simulated previously by Phillips and Donner (2006. Elevated concentrations of insoluble organic aerosol, boosted by a factor of 100 beyond their usual values for this continental region, are found to influence significantly the following quantities: (1 the average numbers and sizes of ice crystals and droplets in the clouds; (2 the horizontal cloud coverage in the free troposphere; (3 precipitation at the ground; and (4 incident solar insolation at the surface. This factor of 100 is plausible for natural fluctuations of the concentration of insoluble organic aerosol, in view of variability of cell concentrations for airborne bacteria seen by Lindemann et al. (1982.

    In nature, such boosting of the insoluble organic aerosol loading could arise from enhanced emissions of biological aerosol particles from a land surface. Surface wetness and solar insolation at the ground are meteorological quantities known to influence rates of growth of

  9. Lepidopterans as potential agents for the biological control of the invasive plant, Miconia calvescens.

    Science.gov (United States)

    Morais, Elisangela G F; Picanço, Marcelo C; Semeão, Altair A; Barreto, Robert W; Rosado, Jander F; Martins, Julio C

    2012-01-01

    This work investigated eight species of Lepidoptera associated with Miconia calvescens DC. (Myrtales: Melastomataceae) in Brazil, including six defoliators, Salbia lotanalis Druce (Lepidoptera: Pyralidae), Druentia inscita Schaus (Mimallonidae), Antiblemma leucocyma Hampson (Noctuidae), three Limacodidae species, a fruit borer Carposina cardinata Meyrick (Carposinidae), and a damager of flowers Pleuroprucha rudimentaria Guenée (Geometridae). Based on host specificity and the damage caused to plants, S. lotanalis and D. inscita are the most promising species for biological control of M. calvescens. Furthermore, if C. cardinata and P. rudimentaria have host specificity in future tests, these caterpillars could also be considered as appropriate biocontrol agents. PMID:22938203

  10. Microbial degradation of trichloroethylene in the rhizosphere: Potential application to biological remediation of waste sites

    International Nuclear Information System (INIS)

    The possibility that vegetation may be used to actively promote microbial restoration of chemically contaminated soils was tested by using rhizosphere and nonvegetated soils collected from a trichloroethylene (TCE)-contaminated field site. Biomass determinations, disappearance of TCE from the headspace of spiked soil slurries, and mineralization of [14C]TCE to 14CO2 all showed that microbial activity is greater in rhizosphere soils and that TCE degradation occurs faster in the rhizosphere than in the edaphosphere. Thus, vegetation may be an important variable in the biological restoration of surface and near-surface soils

  11. Synthetic Biology Tools for the Membrane – Targeted Localisation and Elucidation of Protein Interactions

    DEFF Research Database (Denmark)

    Wendel, Sofie; Seppala, Susanna; Nørholm, Morten

    2014-01-01

    To meet the need for new, green production scenarios, development of biological cell factories is becoming increasingly important. In order for cell factories to compete with traditional production means, it is essential to expand the available toolbox. We are developing tools for the E. coli cell...

  12. Microscopy Images as Interactive Tools in Cell Modeling and Cell Biology Education

    Science.gov (United States)

    Araujo-Jorge, Tania C.; Cardona, Tania S.; Mendes, Claudia L. S.; Henriques-Pons, Andrea; Meirelles, Rosane M. S.; Coutinho, Claudia M. L. M.; Aguiar, Luiz Edmundo V.; Meirelles, Maria de Nazareth L.; de Castro, Solange L.; Barbosa, Helene S.; Luz, Mauricio R. M. P.

    2004-01-01

    The advent of genomics, proteomics, and microarray technology has brought much excitement to science, both in teaching and in learning. The public is eager to know about the processes of life. In the present context of the explosive growth of scientific information, a major challenge of modern cell biology is to popularize basic concepts of…

  13. The study of interaction potentials and differential cross sections for collisions between He atoms and hydrogen halide molecules

    Institute of Scientific and Technical Information of China (English)

    孙桂华; 杨向东; 朱俊; 王彩霞

    2002-01-01

    In this paper, we present the uniform interaction potentials for helium atoms and halogen hydride molecules (HF,HC1 and HBr). The differential cross sections are calculated using the above interaction potentials for the He-HF,HCl and HBr systems, respectively, and the results of the calculations are found to be in agreement with the existingtheoretical results and experimental data.

  14. Synthesis, Characterization and Functionalization of Polymeric Nanoparticles and Investigation of the Interaction with Biological Systems

    International Nuclear Information System (INIS)

    One of the main goals of nanomedicine is to improve the treatment of hazardous diseases whose conventional therapy often has serious side effects. The vision is to create a theranostic drug delivery system which is capable of safely transporting therapeutic cargo through the body to a targeted site of disease at which point the drug is released. Furthermore, it is desirable to track the carrier in real time which would allow for a personal adjustment of the therapy. Studies on the behavior of nanoparticulate substances in a physiological environment form the basis for the possibility to successfully develop a drug carrier system. In the present work, polymeric nanoparticles with different morphologies were prepared by the controlled self-assembly of amphiphilic block copolymers. The nanoparticles were subsequently characterized and their interactions with human cells and serum proteins investigated. A cytotoxicity study with spherical and cylindrical micelles as well as vesicular structures was carried out and showed a dependency of cytotoxic effects on the geometry and size of the nanoparticles. The agglomeration behavior of various polymeric nanoparticles in the presence of serum proteins was also studied. Highly uniform polymeric vesicles were continuously manufactured in a micromixer based device and in situ loading with different components was performed. In this way, dual loaded vesicles with the anticancer drug camptothecin and a high amount of hydrophobic iron oxide nanoparticles were produced. When tested in vitro, these drug-loaded vesicles showed an increased cytotoxic activity against the cancer cell line PC-3 when compared to the free drug. Specific cellular uptake in PC-3 cancer cells was demonstrated with flow cytometry and confocal laser scanning microscopy after functionalization with a cancer cell specific targeting peptide and an additional fluorescent label. Magnetic characterization of the iron oxide-loaded vesicles also confirmed the potential

  15. Interaction grand potential between calcium-silicate-hydrate nanoparticles at the molecular level.

    Science.gov (United States)

    Bonnaud, Patrick A; Labbez, Christophe; Miura, Ryuji; Suzuki, Ai; Miyamoto, Naoto; Hatakeyama, Nozomu; Miyamoto, Akira; Van Vliet, Krystyn J

    2016-02-21

    Calcium-silicate-hydrate (or C-S-H), an inosilicate, is the major binding phase in cement pastes and concretes and a porous hydrated material made up of a percolated and dense network of crystalline nanoparticles of a mean apparent spherical diameter of ∼5 nm that are each stacks of multiple C-S-H layers. Interaction forces between these nanoparticles are at the origin of C-S-H chemical, physical, and mechanical properties at the meso- and macroscales. These particle interactions and the resulting properties may be affected significantly by nanoparticle density and environmental conditions such as the temperature, relative humidity, or concentration of chemical species in the bulk solution. In this study, we combined grand canonical Monte Carlo simulations and an extension of the mean force integration method to derive the pair potentials. This approach enables realistic simulation of the physical environment surrounding the C-S-H particles. We thus constructed the pair potentials for C-S-H nanoparticles of defined chemical stoichiometry at 10% relative humidity (RH), varying the relative crystallographic orientations at a constant particle density of ρpart ∼ 2.21 mmol L(-1). We found that cohesion between nanoparticles is affected strongly by both the aspect ratio and the crystallographic misorientation of interacting particles. This method and the findings underscore the importance of accounting for relative dimensions and orientation among C-S-H nanoparticles in descriptions of physical and simulated multiparticle aggregates or mesoscale systems. PMID:26866999

  16. A method for computing the inter-residue interaction potentials for reduced amino acid alphabet

    Indian Academy of Sciences (India)

    Abhinav Luthra; Anupam Nath Jha; G K Ananthasuresh; Saraswathi Vishveswara

    2007-08-01

    Inter-residue potentials are extensively used in the design and evaluation of protein structures. However, dealing with all (20×20) interactions becomes computationally difficult in extensive investigations. Hence, it is desirable to reduce the alphabet of 20 amino acids to a smaller number. Currently, several methods of reducing the residue types exist; however a critical assessment of these methods is not available. Towards this goal, here we review and evaluate different methods by comparing with the complete (20×20) matrix of Miyazawa-Jernigan potential, including a method of grouping adopted by us, based on multi dimensional scaling (MDS). The second goal of this paper is the computation of inter-residue interaction energies for the reduced amino acid alphabet, which has not been explicitly addressed in the literature until now. By using a least squares technique, we present a systematic method of obtaining the interaction energy values for any type of grouping scheme that reduces the amino acid alphabet. This can be valuable in designing the protein structures.

  17. Accuracy of simple folding model in the calculation of the direct part of real − interaction potential

    Indian Academy of Sciences (India)

    Keshab C Panda; Binod C Sahu; Jhasaketan Bhoi

    2014-05-01

    The direct part of real − interaction potential is calculated in the simple folding model using density-dependent Brink–Boeker effective interaction. The simple folding potentials calculated from the short- and finite-range components of this effective interaction are compared with their corresponding double folding results obtained from the oscillator model wave function to establish the relative accuracy of the model. It is found that the direct part of real – interaction potential calculated in the simple folding model is reliable.

  18. Optimization of enzymatic production of anti-diabetic peptides from black bean (Phaseolus vulgaris L.) proteins, their characterization and biological potential.

    Science.gov (United States)

    Mojica, Luis; de Mejía, Elvira González

    2016-02-01

    The aim was to optimize the production of bioactive peptides from black bean (Phaseolus vulgaris L.) protein isolate and to determine their biological potential using biochemical and in silico approaches. Protein fractions were generated using eight commercially available proteases after 2, 3 and 4 h and 1:20, 1:30 and 1:50 enzyme/substrate (E/S) ratios. The best combination of conditions to generate anti-diabetic peptides was with alcalase for 2 h and E/S of 1:20; with inhibition values for dipeptidyl peptidase IV (DPP-IV, 96.7%), α-amylase (53.4%) and α-glucosidase (66.1%). Generated peptides were characterized using LC-ESI-MS/MS. Molecular docking analysis was performed to predict individual peptide biological potential using DockingServer®. Peptides EGLELLLLLLAG, AKSPLF and FEELN inhibited DPP-IV more efficiently in silico through free energy interactions of -9.8, -9.6 and -9.5 kcal mol(-1), respectively, than the control sitagliptin (-8.67 kcal mol(-1)). The peptide TTGGKGGK (-8.97 kcal mol(-1)) had higher inhibitory potential on α-glucosidase compared to the control acarbose (-8.79 kcal mol(-1)). Peptides AKSPLF (-10.2 kcal mol(-1)) and WEVM (-10.1 kcal mol(-1)) generated a lower free energy interaction with the catalytic site of α-amylase in comparison with acarbose (-9.71 kcal mol(-1)). Bean peptides inhibited the tested enzymes through hydrogen bonds, polar and hydrophobic interactions. The main bindings on the catalytic site were with ASP192, GLU192 and ARG 253 on DPP-IV; TYR151, HIS201 and ILE235 on α-amylase; and ASP34, THR83 and ASN32 on α-glucosidase. For the first time, a systematic evaluation and characterization of the anti-diabetic peptides from black bean protein isolate is presented with the potential for inhibiting important molecular markers related to diabetes. PMID:26824775

  19. Assessment of potential drug–drug interactions and its associated factors in the hospitalized cardiac patients

    Directory of Open Access Journals (Sweden)

    Ghulam Murtaza

    2016-03-01

    Full Text Available Drug–drug interactions (DDIs may result in the alteration of therapeutic response. Sometimes they may increase the untoward effects of many drugs. Hospitalized cardiac patients need more attention regarding drug–drug interactions due to complexity of their disease and therapeutic regimen. This research was performed to find out types, prevalence and association between various predictors of potential drug–drug interactions (pDDIs in the Department of Cardiology and to report common interactions. This study was performed in the hospitalized cardiac patients at Ayub Teaching Hospital, Abbottabad, Pakistan. Patient charts of 2342 patients were assessed for pDDIs using Micromedex® Drug Information. Logistic regression was applied to find predictors of pDDIs. The main outcome measure in the study was the association of the potential drug–drug interactions with various factors such as age, gender, polypharmacy, and hospital stay of the patients. We identified 53 interacting-combinations that were present in total 5109 pDDIs with median number of 02 pDDIs per patient. Overall, 91.6% patients had at least one pDDI; 86.3% were having at least one major pDDI, and 84.5% patients had at least one moderate pDDI. Among 5109 identified pDDIs, most were of moderate (55% or major severity (45%; established (24.2%, theoretical (18.8% or probable (57% type of scientific evidence. Top 10 common pDDIs included 3 major and 7 moderate interactions. Results obtained by multivariate logistic regression revealed a significant association of the occurrence of pDDIs in patient with age of 60 years or more (p < 0.001, hospital stay of 7 days or longer (p < 0.001 and taking 7 or more drugs (p < 0.001. We found a high prevalence for pDDIs in the Department of Cardiology, most of which were of moderate severity. Older patients, patients with longer hospital stay and with elevated number of prescribed drugs were at higher risk of pDDIs.

  20. A Biological Security Motivation System for Potential Threats: Are There Implications for Policy-Making?

    OpenAIRE

    Woody, Erik Z.; Henry eSzechtman

    2013-01-01

    Research indicates that there is a specially adapted, hard-wired brain circuit, the security motivation system, which evolved to manage potential threats, such as the possibility of contamination or predation. The existence of this system may have important implications for policy-making related to security. The system is sensitive to partial, uncertain cues of potential danger, detection of which activates a persistent, potent motivational state of wariness or anxiety. This state motivates ...

  1. The Potential of the South American Leaf Blight as a Biological Agent

    OpenAIRE

    Oghenekome Onokpise; Clifford Louime

    2012-01-01

    When asked by the Department of Homeland Security to create potential terrorism scenarios, even “Out of the Box Thinkers” initially failed to come up with the following scenario. Oil tankers, refineries, nuclear plants, etc., are obvious potential terrorists’ targets, and adequate measures are being taken to protect them. However, what if the target were to be a non-food commodity product, such as natural rubber tree plantations located in places as remote as sou...

  2. Biological performance of functionalized biomedical polymers for potential applications as intraocular lens.

    Science.gov (United States)

    Zheng, Zhiwen; Wang, Yingjun; Jiao, Yan; Zhai, Zhichen

    2016-08-01

    To study the biological performance of surface-modified biomedical polymer materials, a model of the functional mechanism of nonspecific adsorption resistance was constructed. Cell behavior on the surface and in vivo transplantation features of intraocular lens (IOL) materials, such as hydrophobic acrylic ester and polymethyl methacrylate (PMMA), were investigated. The results of cell adhesion and proliferation studies showed that the addition of hirudin can significantly resist epithelial cell adhesion, better than the pure amination process, and thereby inhibit excessive proliferation on the surface. Experiments on the eyes of rabbits indicated that the IOL surfaces with hirudin modification reduced the incidence of cell aggregation and inflammation. Combined with a study of protein-resistant layer construction with recombinant hirudin on the material surface, the mechanism of surface functionalization was determined. The biological performance indicated that nonspecific adsorption is greatly decreased due to the existence of amphiphilic ions or hydration layers, which lead to stability and long-term resistance to nonspecific adsorption. These results offer a theoretical basis for the use of traditional biomedical polymer materials in long-term clinical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1961-1967, 2016.

  3. Mechanical-biological treatment: performance and potentials. An LCA of 8 MBT plants including waste characterization.

    Science.gov (United States)

    Montejo, Cristina; Tonini, Davide; Márquez, María del Carmen; Astrup, Thomas Fruergaard

    2013-10-15

    In the endeavour of avoiding presence of biodegradable waste in landfills and increasing recycling, mechanical-biological treatment (MBT) plants have seen a significant increase in number and capacity in the last two decades. The aim of these plants is separating and stabilizing the quickly biodegradable fraction of the waste as well as recovering recyclables from mixed waste streams. In this study the environmental performance of eight MBT-based waste management scenarios in Spain was assessed by means of life cycle assessment. The focus was on the technical and environmental performance of the MBT plants. These widely differed in type of biological treatment and recovery efficiencies. The results indicated that the performance is strongly connected with energy and materials recovery efficiency. The recommendation for upgrading and/or commissioning of future plants is to optimize materials recovery through increased automation of the selection and to prioritize biogas-electricity production from the organic fraction over direct composting. The optimal strategy for refuse derived fuel (RDF) management depends upon the environmental compartment to be prioritized and the type of marginal electricity source in the system. It was estimated that, overall, up to ca. 180-190 kt CO2-eq. y(-1) may be saved by optimizing the MBT plants under assessment. PMID:23850761

  4. Computation of Ship Hydrodynamic Interaction Forces in Restricted Waters using Potential Theory

    Institute of Scientific and Technical Information of China (English)

    Xueqian Zhou; Serge Sutulo; C. Guedes Soares

    2012-01-01

    A computer code based on the double-body potential flow model and the classic source panel method has been developed to study various problems of hydrodynamic interaction between ships and other objects with solid boundaries including the seabed.A peculiarity of the proposed implementation is the application of the so-called “moving-patch” method for simulating steady boundaries of large extensions.The method is based on an assumption that at any moment just the part of the boundary (“moving patch”) which lies close to the interacting ship is significant for the near-field interaction.For a specific case of the flat bottom,comparative computations were performed to determine optimal dimensions of the patch and of the constituting panels based on the trade-off between acceptable accuracy and reasonable efficiency.The method was applied to estimate the sway force on a ship hull moving obliquely across a dredged channel.The method was validated for a case of ship-to-ship interaction when tank data were available.This study also contains a description of a newly developed spline approximation algorithm necessary for creating consistent discretizations of ship hulls with various degrees of refinement.

  5. Improving intermolecular interactions in DFTB3 using extended polarization from chemical-potential equalization

    CERN Document Server

    Christensen, Anders S; Cui, Qiang

    2015-01-01

    Semi-empirical quantum mechanical methods traditionally expand the electron density in a minimal, valence-only electron basis set. The minimal-basis approximation causes molecular polarization to be underestimated, and hence intermolecular interaction energies are also underestimated, especially for intermolecular interactions involving charged species. In this work, the third-order self-consistent charge density functional tight-binding method (DFTB3) is augmented with an auxiliary response density using the chemical-potential equalization (CPE) method and an empirical dispersion correction (D3). The parameters in the CPE and D3 models are fitted to high-level CCSD(T) reference interaction energies for a broad range of chemical species, as well as dipole moments calculated at the DFT level; the impact of including polarizabilities of molecules in the parameterization is also considered. Parameters for the elements H, C, N, O and S are presented. The RMSD interaction energy is improved from 6.07 kcal/mol to 1...

  6. Entangling spin-spin interactions of ions in individually controlled potential wells

    Science.gov (United States)

    Wilson, Andrew; Colombe, Yves; Brown, Kenton; Knill, Emanuel; Leibfried, Dietrich; Wineland, David

    2014-03-01

    Physical systems that cannot be modeled with classical computers appear in many different branches of science, including condensed-matter physics, statistical mechanics, high-energy physics, atomic physics and quantum chemistry. Despite impressive progress on the control and manipulation of various quantum systems, implementation of scalable devices for quantum simulation remains a formidable challenge. As one approach to scalability in simulation, here we demonstrate an elementary building-block of a configurable quantum simulator based on atomic ions. Two ions are trapped in separate potential wells that can individually be tailored to emulate a number of different spin-spin couplings mediated by the ions' Coulomb interaction together with classical laser and microwave fields. We demonstrate deterministic tuning of this interaction by independent control of the local wells and emulate a particular spin-spin interaction to entangle the internal states of the two ions with 0.81(2) fidelity. Extension of the building-block demonstrated here to a 2D-network, which ion-trap micro-fabrication processes enable, may provide a new quantum simulator architecture with broad flexibility in designing and scaling the arrangement of ions and their mutual interactions. This research was funded by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA), ONR, and the NIST Quantum Information Program.

  7. Assessment of Potential Herb-Drug Interactions among Nigerian Adults with Type-2 Diabetes.

    Science.gov (United States)

    Ezuruike, Udoamaka; Prieto, Jose M

    2016-01-01

    It is becoming increasingly evident that patients with diabetes do not rely only on prescription drugs for their disease management. The use of herbal medicines is one of the self-management practices adopted by these patients, often without the knowledge of their healthcare practitioners. This study assessed the potential for pharmacokinetic herb-drug interactions (HDIs) amongst Nigerian adult diabetic patients. This was done through a literature analysis of the pharmacokinetic profile of their herbal medicines and prescription drugs, based on information obtained from 112 patients with type-2 diabetes attending two secondary health care facilities in Nigeria. Fifty percent of the informants used herbal medicines alongside their prescription drugs. Worryingly, 60% of the patients taking herbal medicines did not know their identity, thus increasing the risk of unidentified HDIs. By comparing the pharmacokinetic profile of eight identified herbs taken by the patients for the management of diabetes against those of the prescription drugs, several scenarios of potential HDIs were identified and their clinical relevance is discussed. The lack of clinical predictors points toward cultural factors as the influence for herb use, making it more difficult to identify these patients and in turn monitor potential HDIs. In identifying these possible interactions, we have highlighted the need for healthcare professionals to promote a proactive monitoring of patients' use of herbal medicines. PMID:27559312

  8. The prospects for producing ultracold NH$_3$ molecules by sympathetic cooling: a survey of interaction potentials

    CERN Document Server

    Zuchowski, Piotr S \\

    2008-01-01

    We investigate the possibility of producing ultracold NH3 molecules by sympathetic cooling in a bath of ultracold atoms. We consider the interactions of NH3 with alkali-metal and alkaline-earth atoms, and with Xe, using ab initio coupled-cluster calculations. For Rb-NH3 and Xe-NH3 we develop full potential energy surfaces, while for the other systems we characterize the stationary points (global and local minima and saddle points). We also calculate isotropic and anisotropic Van der Waals C6 coefficients for all the systems. The potential energy surfaces for interaction of NH3 with alkali-metal and alkaline-earth atoms all show deep potential wells and strong anisotropies. The well depths vary from 887 1/cm for Mg-NH3 to 5104 1/cm for Li-NH3. This suggests that all these systems will exhibit strong inelasticity whenever inelastic collisions are energetically allowed and that sympathetic cooling will work only when both the atoms and the molecules are already in their lowest internal states. Xe-NH3 is more wea...

  9. Influence of Solvent-Solvent and Solute-Solvent Interaction Properties on Solvent-Mediated Potential

    Institute of Scientific and Technical Information of China (English)

    ZHOU Shi-Qi

    2005-01-01

    A recently proposed universal calculational recipe for solvent-mediated potential is applied to calculate excess potential of mean force between two large Lennard-Jones (LJ) or hard core attractive Yukawa particles immersed in small LJ solvent bath at supercritical state. Comparison between the present prediction with a hypernetted chain approximation adopted for solute-solute correlation at infinitely dilute limit and existing simulation data shows high accuracy for the region with large separation, and qualitative reliability for the solute particle contact region. The calculational simplicity of the present recipe allows for a detailed investigation on the effect of the solute-solvent and solvent-solvent interaction details on the excess potential of mean force. The resultant conclusion is that gathering of solvent particles near a solute particle leads to repulsive excess PMF, while depletion of solvent particles away from the solute particle leads to attractive excess PMF, and minor change of the solvent-solvent interaction range has large influence on the excess PMF.

  10. Assessment of Potential Herb-Drug Interactions among Nigerian Adults with Type-2 Diabetes

    Science.gov (United States)

    Ezuruike, Udoamaka; Prieto, Jose M.

    2016-01-01

    It is becoming increasingly evident that patients with diabetes do not rely only on prescription drugs for their disease management. The use of herbal medicines is one of the self-management practices adopted by these patients, often without the knowledge of their healthcare practitioners. This study assessed the potential for pharmacokinetic herb-drug interactions (HDIs) amongst Nigerian adult diabetic patients. This was done through a literature analysis of the pharmacokinetic profile of their herbal medicines and prescription drugs, based on information obtained from 112 patients with type-2 diabetes attending two secondary health care facilities in Nigeria. Fifty percent of the informants used herbal medicines alongside their prescription drugs. Worryingly, 60% of the patients taking herbal medicines did not know their identity, thus increasing the risk of unidentified HDIs. By comparing the pharmacokinetic profile of eight identified herbs taken by the patients for the management of diabetes against those of the prescription drugs, several scenarios of potential HDIs were identified and their clinical relevance is discussed. The lack of clinical predictors points toward cultural factors as the influence for herb use, making it more difficult to identify these patients and in turn monitor potential HDIs. In identifying these possible interactions, we have highlighted the need for healthcare professionals to promote a proactive monitoring of patients' use of herbal medicines. PMID:27559312

  11. Interaction of interleukin-5 with its receptors on murine leukemic BCL1 cells and its implication in biological activity

    International Nuclear Information System (INIS)

    Interaction of interleukin (IL)-5 with its receptors on murine leukemic cell line, BCL1 cells was examined. 125I-labeled recombinant murine IL-5(rmIL-5) bound specifically to high-affinity receptors on BCL1 cells. rmIL-5, which was about 2500-fold more active than recombinant human IL-5(rhIL-5) in IgM-inducing activity on BCL1 cells, also showed about 5000-fold higher affinity to receptors. These results suggest that the bioactivity of IL-5 correlates with its receptor-binding activity. When disulfide bond formation was blocked, rmIL-5 dissociated into a monomer and lost its biological activity. This monomeric form of rmIL-5 also lost its ability to bind to cells, suggesting that dimer formation is essential for the biological activity of IL-5

  12. Protocols for assessing radiofrequency interactions with gold nanoparticles and biological systems for non-invasive hyperthermia cancer therapy.

    Science.gov (United States)

    Corr, Stuart J; Cisneros, Brandon T; Green, Leila; Raoof, Mustafa; Curley, Steven A

    2013-08-28

    Cancer therapies which are less toxic and invasive than their existing counterparts are highly desirable. The use of RF electric-fields that penetrate deep into the body, causing minimal toxicity, are currently being studied as a viable means of non-invasive cancer therapy. It is envisioned that the interactions of RF energy with internalized nanoparticles (NPs) can liberate heat which can then cause overheating (hyperthermia) of the cell, ultimately ending in cell necrosis. In the case of non-biological systems, we present detailed protocols relating to quantifying the heat liberated by highly-concentrated NP colloids. For biological systems, in the case of in vitro experiments, we describe the techniques and conditions which must be adhered to in order to effectively expose cancer cells to RF energy without bulk media heating artifacts significantly obscuring the data. Finally, we give a detailed methodology for in vivo mouse models with ectopic hepatic cancer tumors.

  13. Population biology of multispecies helminth infection: interspecific interactions and parasite distribution

    OpenAIRE

    Bottomley, C.; Isham, V.; Basanez, M. G.

    2005-01-01

    Despite evidence for the existence of interspecific interactions between helminth species, there has been no theoretical exploration of their effect on the distribution of the parasite species in a host population. We use a deterministic model for the accumulation and loss of adult worms of 2 interacting helminth species to motivate an individual-based stochastic model. The mean worm burden and variance: mean ratio (VMR) of each species, and the correlation between the two species are used to...

  14. Matter-Wave Solitons in Two-Component Bose-Einstein Condensates with Tunable Interactions and Time Varying Potential

    Institute of Scientific and Technical Information of China (English)

    宣恒农; 左苗

    2011-01-01

    We present three families of exact matter-wave soliton solutions for an effective one-dimension two- component Bose-Einstein condensates (BECs) with tunable interactions, harmonic potential and gain or loss term. We investigate the dynamics of bright-bright solitons, bright-dark solitons and dark-dark solitons for the time-dependent expulsive harmonic trap potential, periodically modulated harmonic trap potential, and kinklike modulated harmonic trap potential. Through the Feshbach resonance, these dynamics can be realized in experiments by suitable control of time-dependent trap parameters, atomic interactions, and interaction with thermal cloud.

  15. Baryon interactions in lattice QCD: the direct method vs. the HAL QCD potential method

    CERN Document Server

    Iritani, Takumi

    2016-01-01

    We make a detailed comparison between the direct method and the HAL QCD potential method for the baryon-baryon interactions, taking the $\\Xi\\Xi$ system at $m_\\pi= 0.51$ GeV in 2+1 flavor QCD and using both smeared and wall quark sources. The energy shift $\\Delta E_\\mathrm{eff}(t)$ in the direct method shows the strong dependence on the choice of quark source operators, which means that the results with either (or both) source are false. The time-dependent HAL QCD method, on the other hand, gives the quark source independent $\\Xi\\Xi$ potential, thanks to the derivative expansion of the potential, which absorbs the source dependence to the next leading order correction. The HAL QCD potential predicts the absence of the bound state in the $\\Xi\\Xi$($^1$S$_0$) channel at $m_\\pi= 0.51$ GeV, which is also confirmed by the volume dependence of finite volume energy from the potential. We also demonstrate that the origin of the fake plateau in the effective energy shift $\\Delta E_\\mathrm{eff}(t)$ at $t \\sim 1$ fm can b...

  16. Solid phase stability of a double-minimum interaction potential system

    Energy Technology Data Exchange (ETDEWEB)

    Suematsu, Ayumi; Yoshimori, Akira, E-mail: a.yoshimori@cmt.phys.kyushu-u.ac.jp; Saiki, Masafumi; Matsui, Jun [Department of Physics, Kyushu University, Fukuoka 812-8581 (Japan); Odagaki, Takashi [School of Science and Engineering, Tokyo Denki University, Hatoyama, Saitama 350-0394 (Japan)

    2014-06-28

    We study phase stability of a system with double-minimum interaction potential in a wide range of parameters by a thermodynamic perturbation theory. The present double-minimum potential is the Lennard-Jones-Gauss potential, which has a Gaussian pocket as well as a standard Lennard-Jones minimum. As a function of the depth and position of the Gaussian pocket in the potential, we determine the coexistence pressure of crystals (fcc and bcc). We show that the fcc crystallizes even at zero pressure when the position of the Gaussian pocket is coincident with the first or third nearest neighbor site of the fcc crystal. The bcc crystal is more stable than the fcc crystal when the position of the Gaussian pocket is coincident with the second nearest neighbor sites of the bcc crystal. The stable crystal structure is determined by the position of the Gaussian pocket. These results show that we can control the stability of the solid phase by tuning the potential function.

  17. THE MECHANISM OF INTERACTION OF EXTERNAL ELECTROMAGNETIC FIELDS ON THE PROCESSES THAT STIMULATE THE ACTIVITY OF BIOLOGICAL OBJECTS

    Directory of Open Access Journals (Sweden)

    Kurzin N. N.

    2015-04-01

    Full Text Available For explaining the regulatory mechanisms of biological the methods of classical biology, chemistry and physics are clearly inadequate, since the structure and function of these mechanisms are determined by the motion of the electron clouds in conjugated molecules. This "movement" can lead eventually to a complex organization called life only if they are subject to certain static laws and, therefore, may eventually be known in all the complexity of their relationships. Biological objects, resulting in the evolution of the environment, are like a part of that environment. Information stored in the seed, based in its deployment on energy and material resources of the environment. Moreover, in the process of development body derives more information from the environment. Nature has the extreme complexity and diversity. Examples include a huge variety of organisms, the complexity of atomic processes, the structure of the solar system and the stellar galaxies. There are four types of different interactions with the help of which we describe all physical phenomena. Today, it seems to us that all the various manifestations of the nature of elementary particles are reduced to the action between them of these four kinds of forces. The most famous of these are the gravitational Zion and electromagnetic forces, which are directly manifested in the world around us. Gravity allows us to stay on the Earth and allows planets to stay in their orbits. Electromagnetic interactions of electrons inside atoms and molecules cause all known chemical and physical properties of ordinary solids, liquids and gases and, in addition, are the basis of all of the processes occurring in living organisms. Research in the field of magneto proved that the biological systems are selectively susceptible to the action of electromagnetic fields as a function of their intensity, exposure time and frequency

  18. Maize benefits the predatory beetle, Propylea japonica (Thunberg, to provide potential to enhance biological control for aphids in cotton.

    Directory of Open Access Journals (Sweden)

    Fang Ouyang

    Full Text Available BACKGROUND: Biological control provided by natural enemies play an important role in integrated pest management. Generalist insect predators provide an important biological service in the regulation of agricultural insect pests. Our goal is to understand the explicit process of oviposition preference, habitat selection and feeding behavior of predators in farmland ecosystem consisting of multiple crops, which is central to devising and delivering an integrated pest management program. METHODOLOGY: The hypotheses was that maize can serve as habitat for natural enemies and benefits predators to provide potential to enhance biological control for pest insects in cotton. This explicit process of a predatory beetle, Propylea japonica, in agricultural ecosystem composed of cotton and maize were examined by field investigation and stable carbon isotope analysis during 2008-2010. PRINCIPAL FINDING: Field investigation showed that P. japonica adults will search host plants for high prey abundance before laying eggs, indicating indirectly that P. japonica adults prefer to inhabit maize plants and travel to cotton plants to actively prey on aphids. The δ(13C values of adult P. japonica in a dietary shift experiment found that individual beetles were shifting from a C(3- to a C(4-based diet of aphids reared on maize or cotton, respectively, and began to reflect the isotope ratio of their new C(4 resources within one week. Approximately 80-100% of the diet of P. japonica adults in maize originated from a C(3-based resource in June, July and August, while approximately 80% of the diet originated from a C(4-based resource in September. CONCLUSION/SIGNIFICANCE: Results suggest that maize can serve as a habitat or refuge source for the predatory beetle, P. japonica, and benefits predators to provide potential to enhance biological control for insect pests in cotton.

  19. Autofluorescence of atmospheric bioaerosols - fluorescent biomolecules, biological standard particles and potential interferences

    Science.gov (United States)

    Pöhlker, C.; Huffmann, J. A.; Pöschl, U.

    2012-04-01

    Primary biological aerosol particles (PBAP) such as pollen, fungal spores, bacteria, biogenic polymers and debris from larger organisms are known to influence atmospheric chemistry and physics, the biosphere and public health. PBAP account for up to ~30% of fine and up to ~70% of coarse particulate matter in urban, rural and pristine environment and are released with estimated emission rates of up to ~1000 Tg/a [1]. Continuous measurements of the abundance, variability and diversity of PBAP have been difficult until recently, however. The application of on-line instruments able to detect autofluorescence from biological particles in real-time has been a promising development for the measurement of PBAP concentrations and fluxes in different environments [2,3]. The detected fluorescent biological aerosol particles (FBAP) can be regarded as a subset of PBAP, although the exact relationship between PBAP and FBAP is still being investigated. Autofluorescence of FBAP is usually a superposition of fluorescence from a mixture of individual fluorescent molecules (fluorophores). Numerous biogenic fluorophores such as amino acids (e.g., tryptophan, tyrosine), coenzymes (e.g., NAD(P)H, riboflavin) and biopolymers (e.g., cellulose) emit fluorescent light due to heterocyclic aromatic rings or conjugated double bonds within their molecular structures. The tryptophan emission peak is a common feature of most bioparticles because the amino acid is a constituent of many proteins and peptides. The influence of the coenzymes NAD(P)H and riboflavin on the autofluorescence of bacteria can be regarded as an indicator for bacterial metabolism and has been utilized to discriminate between viable and non-viable organisms [4]. However, very little information is available about other essential biofluorophores in fungal spores and pollen. In order to better understand the autofluorescence behavior of FBAP, we have used fluorescence spectroscopy and fluorescence microscopy to analyze standard

  20. Hypertension is associated with marked alterations in sphingolipid biology: a potential role for ceramide.

    Directory of Open Access Journals (Sweden)

    Léon J A Spijkers

    Full Text Available BACKGROUND: Hypertension is, amongst others, characterized by endothelial dysfunction and vascular remodeling. As sphingolipids have been implicated in both the regulation of vascular contractility and growth, we investigated whether sphingolipid biology is altered in hypertension and whether this is reflected in altered vascular function. METHODS AND FINDINGS: In isolated carotid arteries from spontaneously hypertensive rats (SHR and normotensive Wistar-Kyoto (WKY rats, shifting the ceramide/S1P ratio towards ceramide dominance by administration of a sphingosine kinase inhibitor (dimethylsphingosine or exogenous application of sphingomyelinase, induced marked endothelium-dependent contractions in SHR vessels (DMS: 1.4±0.4 and SMase: 2.1±0.1 mN/mm; n = 10, that were virtually absent in WKY vessels (DMS: 0.0±0.0 and SMase: 0.6±0.1 mN/mm; n = 9, p<0.05. Imaging mass spectrometry and immunohistochemistry indicated that these contractions were most likely mediated by ceramide and dependent on iPLA(2, cyclooxygenase-1 and thromboxane synthase. Expression levels of these enzymes were higher in SHR vessels. In concurrence, infusion of dimethylsphingosine caused a marked rise in blood pressure in anesthetized SHR (42±4%; n = 7, but not in WKY (-12±10%; n = 6. Lipidomics analysis by mass spectrometry, revealed elevated levels of ceramide in arterial tissue of SHR compared to WKY (691±42 vs. 419±27 pmol, n = 3-5 respectively, p<0.05. These pronounced alterations in SHR sphingolipid biology are also reflected in increased plasma ceramide levels (513±19 pmol WKY vs. 645±25 pmol SHR, n = 6-12, p<0.05. Interestingly, we observed similar increases in ceramide levels (correlating with hypertension grade in plasma from humans with essential hypertension (185±8 pmol vs. 252±23 pmol; n = 18 normotensive vs. n = 19 hypertensive patients, p<0.05. CONCLUSIONS: Hypertension is associated with marked alterations in vascular

  1. In vitro and in vivo evaluation of CYP1a interaction potential of terminalia arjuna bark

    Directory of Open Access Journals (Sweden)

    Alice Varghese

    2014-01-01

    Full Text Available Terminalia arjuna Wight and Arn. (Combretaceae is a tree having an extensive medicinal potential in cardiovascular disorders. Triterpenoids are mainly responsible for cardiovascular properties. Aqueous, hydroalcoholic and alcoholic extract of T. arjuna, arjunic acid and arjungenin were examined for their potential to inhibit CYP1A enzyme in rat and human liver microsomes. IC 50 values of aqueous, hydroalcoholic and alcoholic extract of T. arjuna was found to be 11.4, 28.9 and 44.6 μg/ml in rat liver microsomes while 30.0, 29.7 and 39.0 μg/ml in human liver microsomes, respectively for CYP1A. However IC 50 values of arjunic acid and arjungenin for both rat liver microsomes and human liver microsomes were found to be >50 μM. Arjunic acid and arjungenin did not show inhibition of CYP1A enzyme up to concentrations of 50 μM. These in vitro data indicate that Terminalia arjuna extracts contain constituents that can potently inhibit the activity of CYP1A, which could in turn lead to undesirable pharmacokinetic drug-herb interactions in vivo. Based on the in vitro data, interaction potential of the aqueous extract of Terminalia arjuna orally in rats was investigated. A probe substrate, phenacetin, was used to index the activity of CYP1A. In vivo pharmacokinetic study of coadministration of aqueous extract of Terminalia arjuna and phenacetin, revealed that the aqueous extract did not lead to any significant change in the pharmacokinetic parameters of phenacetin as compared with control group. Though there was no in vivo-in vitro correlation, drug interactions could arise with drugs having a narrow therapeutic range and extensively cleared by CYP1A enzyme, which could lead to undesirable side effects.

  2. Thermal and nonThermal Mechanisms of Biological Interaction of Microwaves

    CERN Document Server

    Williams, J M

    2001-01-01

    Research in the past on the biological effects of microwaves often has been based on faulty assumptions. The major flaw has been the premise that microwaves only produce thermal effects in tissue. This premise easily may be proven physically incorrect. Furthermore, assuming only thermal effects leads one to an optimist's error of quantification in which calories are counted instead of joules. Past investigations have been misled both by these assumptions and by stereotyped experiments using only narrow band radiation sources. Recent studies show that wide band microwaves bring out biological effects which are unrelated to those caused by heat flow. A review by Kenneth Foster provides a basis for criticism and improved understanding. PACS: 87.10 87.22 87.50 87.54

  3. Using ANN to predict E. coli accumulation in coves based on interaction amongst various physical, chemical and biological factors

    Science.gov (United States)

    Dwivedi, D.; Mohanty, B. P.; Lesikar, B. J.

    2008-12-01

    The accumulation of Escherichia Coli (E. coli) in canals, coves and streams is the result of a number of interacting processes operating at multiple spatial and temporal scales. Fate and transport of E. coli in surface water systems is governed by different physical, chemical, and biological processes. Various models developed to quantify each of these processes occurring at different scales are not so far pooled into a single predictive model. At present, very little is known about the fate and transport of E. coli in the environment. We hypothesize that E. coli population heterogeneity in canals and coves is affected by physical factors (average stream width and/ depth, secchi depth, flow and flow severity, day since precipitation, aquatic vegetation, solar radiation, dissolved and total suspended solids etc.); chemical factors (basic water quality, nutrients, organic compounds, pH, and toxicity etc.); and biological factors (type of bacterial strain, predation, and antagonism etc.). The specific objectives of this study are to: (1) examine the interactions between E. coli and various coupled physical, chemical and biological factors; (2) examine the interactions between E. coli and toxic organic pollutants and other pathogens (viruses); and (3) evaluate qualitatively the removal efficiency of E. coli. We suggest that artificial neural networks (ANN) may be used to provide a possible solution to this problem. To demonstrate the application of the approach, we develop an ANN representing E. coli accumulation in two polluted sites at Lake Granbury in the upper part of the Brazos River in North Central Texas. The graphical structure of ANN explicitly represents cause- and-effect relationship between system variables. Each of these relationships can then be quantified independently using an approach suitable for the type and scale of information available. Preliminary results revealed that E. coli concentrations in canals show seasonal variations regardless of change

  4. The biological role of a-ketoglutaric acid in physiological processes and its therapeutic potential.

    Science.gov (United States)

    Grzesiak, Paulina; Słupecka-Ziemilska, Monika; Woliński, Jarosław

    2016-01-01

    In this article we present the results of recent studies on the mechanism of action and biological role of α-ketoglutaric acid (AKG) in animals including developmental period of life. AKG is an intermediate in the Krebs cycle, which generates energy for life processes. Administration of AKG has been shown to be beneficial for proper development and function of the skeletal system during growth of young organisms, as well as in adulthood. In the form of a dietary supplement it also contributes to inhibition of osteoporosis in women. Moreover, it promotes the growth of muscle mass and accelerates wound healing. AKG has a significant impact on the morphology of the gastrointestinal tract in healthy animals and animals with damaged gastrointestinal tract mucosa. It is also a promising substance for the treatment of patients with short bowel syndrome, as it stimulates beneficial changes in intestinal morphology. Recent research has also revealed that AKG has neuroprotective effects. PMID:27416627

  5. Biology and potential clinical implications of tissue inhibitor of metalloproteinases-1 in colorectal cancer treatment

    DEFF Research Database (Denmark)

    Sørensen, Nanna Møller; Sørensen, irene Vejgaard; Würtz, Sidse Ørnbjerg;

    2008-01-01

    Colorectal cancer (CRC) is the second leading cause of cancer-related death in the industrialized world. About half of "curatively" resected patients develop recurrent disease within the next 3-5 years despite the lack of clinical, histological and biochemical evidence of remaining overt disease...... after resection of the primary tumour. Availability of validated biological markers for early detection, selection for adjuvant therapy, prediction of treatment efficacy and monitoring of treatment efficacy would most probably increase survival. Tissue inhibitor of metalloproteinases-1 (TIMP-1) may...... patients, suggesting that TIMP-1 could have a tumour-promoting function. Furthermore, measurement of plasma TIMP-1 has been shown to be useful for disease detection, with a high sensitivity and high specificity for early-stage colon cancer. This review describes some basic information on the current...

  6. Aloe vera : Potential candidate in health management via modulation of biological activities

    Directory of Open Access Journals (Sweden)

    Arshad H Rahmani

    2015-01-01

    Full Text Available Treatment based on natural products is rapidly increasing worldwide due to the affordability and fewer side effects of such treatment. Various plants and the products derived from them are commonly used in primary health treatment, and they play a pivotal role in the treatment of diseases via modulation of biochemical and molecular pathways. Aloe vera, a succulent species, produces gel and latex, plays a therapeutic role in health management through antioxidant, antitumor, and anti-inflammatory activities, and also offers a suitable alternative approach for the treatment of various types of diseases. In this review, we summarize the possible mechanism of action and the therapeutic implications of Aloe vera in health maintenance based on its modulation of various biological activities.

  7. Primary Study on Biological Control Potential of Trichoderma harzianum TL-1

    Institute of Scientific and Technical Information of China (English)

    Su; Zhenyu; Xiao; Man; Gao; Xinzheng; Tang; Libo; Li; Li

    2014-01-01

    Trichoderma harzianum is a widely used biocontrol fungus. The growth promoting effect of strain Trichoderma harzianum TL-1 on tomato and pepper and its biological control effects against tomato seedling damping-off and pepper blight were investigated through pot experiments. The results showed that the stain TL-1 had significant promotion effect on growth of pepper and tomato in sterilized and natural soils. With the application dose of 3. 0 and 0. 5g/ pot,their dry weight were increased up to 46% and 150% compared with control,respectively. In addition,TL-1 had good control effects against tomato seedling damping-off and pepper blight. Compared with fungicide treatment,TL-1 treatment could control diseases for long term,without repeat occurrence of diseases.

  8. Biological Interactions during the Life History of Seaweed ―A Microscopic Review―

    OpenAIRE

    Mine, Ichiro

    2008-01-01

    Seaweed is important for human beings as food. From an ecological viewpoint, it also occupies a substantial position as the primary producer in the marine food chain and as a nursery for many marine animals. Fundamental biological features are in great diversity in seaweed. The composition of photosynthetic pigments is distinct among three major groups of seaweed; green, brown and red algae. There is also a wide range of life history patterns including the isomorphic and heteromorphic alterna...

  9. A Biological Security Motivation System for Potential Threats: Are There Implications for Policy-Making?

    Directory of Open Access Journals (Sweden)

    Erik Z Woody

    2013-09-01

    Full Text Available Research indicates that there is a specially adapted, hard-wired brain circuit, the security motivation system, which evolved to manage potential threats, such as the possibility of contamination or predation. The existence of this system may have important implications for policy-making related to security. The system is sensitive to partial, uncertain cues of potential danger, detection of which activates a persistent, potent motivational state of wariness or anxiety. This state motivates behaviours to probe the potential danger, such as checking, and to correct for it, such as washing. Engagement in these behaviours serves as the terminating feedback for the activation of the system. Because security motivation theory makes predictions about what kinds of stimuli activate security motivation and what conditions terminate it, the theory may have applications both in understanding how policy-makers can best influence others, such as the public, and also in understanding the behavior of policy-makers themselves.

  10. Purpureocillium lilacinum, potential agent for biological control of the leaf-cutting ant Acromyrmex lundii.

    Science.gov (United States)

    Goffré, D; Folgarait, P J

    2015-09-01

    Many leaf-cutter ant species are well known pests in Latin America, including species of the genera Acromyrmex and Atta. An environmentally friendly strategy to reduce the number of leafcutter ants and avoid indiscriminate use of chemical pesticides is biological control. In this work we evaluated the effectiveness of a strain of the entomopathogen Purpureocillium lilacinum, against worker ants from six Acromyrmex lundii field colonies, after immersions in pure suspensions at a concentration of 1×10(6)conidiaml(-1). Survival of ants treated with P. lilacinum was significantly lower than that recorded in controls, and median lethal time (LT50) was 6-7days. P. lilacinum was responsible for 85.6% (80.6-89.7) of the mortality in inoculated ants, in which we found that the percentage of other entomopathogens that naturally infected ants decreased also, suggesting a good competitive capability of the fungus. Horizontal transmission to non-inoculated ants was also evidenced, given that 58.5% (41.9-64.2) of them died because of P. lilacinum. Moreover, we tested pathogenicity for three concentrations of this strain (1.0×10(4), 10(6) and 10(8)conidiaml(-1)) and found a significantly faster mortality of ants and greater median percentage of infection at 10(8)conidiaml(-1) of P. lilacinum. CL50 value was 2.8×10(5)conidiaml(-1). We thus propose the use of P. lilacinum as a biological control agent of leafcutter ants in crops and plantations. PMID:26205173

  11. A new method for detecting interactions between the senses in event-related potentials

    DEFF Research Database (Denmark)

    Gondan, Matthias; Röder, B.

    2006-01-01

    Event-related potentials (ERPs) can be used in multisensory research to determine the point in time when different senses start to interact, for example, the auditory and the visual system. For this purpose, the ERP to bimodal stimuli (AV) is often compared to the sum of the ERPs to auditory (A...... not contain common activity: This activity would be subtracted twice from one ERP and would, therefore, contaminate the result. In the present study, ERPs to unimodal, bimodal, and trimodal auditory, visual, and tactile stimuli (T) were recorded. We demonstrate that (T + TAV) - (TA + TV) is equivalent...

  12. Relativistic symmetries in trigonometric Poschl-Teller potential plus tensor interaction

    OpenAIRE

    Falaye, Babatunde J.; Sameer M. Ikhdair

    2013-01-01

    The Dirac equation is solved to obtain its approximate bound states for a spin-1/2 particle in the presence of trigonometric Poschl-Teller (tPT) potential including a Coulomb-like tensor interaction with arbitrary spin-orbit quantum number $\\kappa$ using an approximation scheme to substitute the centrifugal terms k(k+1)/r^2. In view of spin and pseudo-spin (p-spin) symmetries, the relativistic energy eigenvalues and the corresponding two-component wave functions of a particle moving in the fi...

  13. Scalar-field cosmological and collapse models with general self-interaction potentials

    Energy Technology Data Exchange (ETDEWEB)

    Giambo, Roberto; Giannoni, Fabio [Dipartimento di Matematica e Informatica, Universita di Camerino (Italy); Magli, Giulio, E-mail: roberto.giambo@unicam.i, E-mail: fabio.giannoni@unicam.i, E-mail: magli@mate.polimi.i [Dipartimento di Matematica, Politecnico di Milano (Italy)

    2009-10-01

    We present the results of the investigation of a wide class of self-interacting, self-gravitating homogeneous scalar fields models, characterized by quite general conditions on the scalar field potential, and including both asymptotically polynomial and exponential behaviors. We show that the generic evolution is always divergent in a finite time, and this result is used to construct cosmological models as well as radiating collapsing star models of the Vaidya type - for the latter it turns out that black holes are generically formed.

  14. Predicting potential global distributions of two Miscanthus grasses: implications for horticulture, biofuel production, and biological invasions.

    Directory of Open Access Journals (Sweden)

    Heather A Hager

    Full Text Available In many regions, large proportions of the naturalized and invasive non-native floras were originally introduced deliberately by humans. Pest risk assessments are now used in many jurisdictions to regulate the importation of species and usually include an estimation of the potential distribution in the import area. Two species of Asian grass (Miscanthus sacchariflorus and M. sinensis that were originally introduced to North America as ornamental plants have since escaped cultivation. These species and their hybrid offspring are now receiving attention for large-scale production as biofuel crops in North America and elsewhere. We evaluated their potential global climate suitability for cultivation and potential invasion using the niche model CLIMEX and evaluated the models' sensitivity to the parameter values. We then compared the sensitivity of projections of future climatically suitable area under two climate models and two emissions scenarios. The models indicate that the species have been introduced to most of the potential global climatically suitable areas in the northern but not the southern hemisphere. The more narrowly distributed species (M. sacchariflorus is more sensitive to changes in model parameters, which could have implications for modelling species of conservation concern. Climate projections indicate likely contractions in potential range in the south, but expansions in the north, particularly in introduced areas where biomass production trials are under way. Climate sensitivity analysis shows that projections differ more between the selected climate change models than between the selected emissions scenarios. Local-scale assessments are required to overlay suitable habitat with climate projections to estimate areas of cultivation potential and invasion risk.

  15. Identification and biological activity of potential probiotic bacterium isolated from the stomach mucus of breast-fed lamb

    Directory of Open Access Journals (Sweden)

    H. Kiňová Sepov��

    2011-09-01

    Full Text Available The lactic acid bacterium E isolated from the stomach mucus of breast-fed lamb was identified by sequencing of 16S rDNA fragment and species-specific PCR as Lactobacillus reuteri. Its potential antimicrobial activity and ability to modulate immune system in vitro and in vivo was determined. The growth inhibition of potential pathogens decreased from Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enterica ser. Minnesota to Escherichia coli. The lowest inhibition activity was observed in the case of Candida albicans. The ability of L. reuteri E to modulate biological activities of human and mouse mononuclear cells was estimated in vitro and in vivo, respectively. The production of IL-1β by monocytes in vitro was significantly induced by L. reuteri E (relative activity 2.47. The ability to modulate biological activities of mononuclear cells by living L. reuteri E cells in vitro in comparison to disintegrated L. reuteri E cells in vivo differed. For example lysozyme activity in vitro was inhibited while in vivo was stimulated (relative activities 0.30 and 1.83, respectively. The peroxidase activity in vitro was stimulated while in vivo was inhibited (relative activities 1.53 and 0.17, respectively. Obtained results indicate that L. reuteri E is potential candidate to be used in probiotic preparations for animals and/or human.

  16. Baryon-baryon interactions described by the WKB-RGM quark-model potential

    International Nuclear Information System (INIS)

    We investigate the baryon-baryon interactions predicted by the Kyoto-Niigata quark model, by using phase-shift equivalent local potentials obtained in the WKB-RGM method. The effect of flavor symmetry breaking is discussed by comparing the 1S0 potentials among the NN, ΣN(I=3/2), ΣΣ(I=2), ΞΣ(I=3/2) and ΞΞ(I=1) systems, which possess the simple flavor SU3 symmetry (22). It is characterized by the detailed balance between the reduction of the short-range repulsion, generated from the color-magnetic term, and the reduction of the medium-range attraction, generated from scalar-meson exchange. A special role of the Bryan-Scott term in the model fss2 is emphasized. (author)

  17. Isotropization in Bianchi type-I cosmological model with fermions and bosons interacting via Yukawa potential

    CERN Document Server

    Ribas, M O; Devecchi, F P; Kremer, G M

    2015-01-01

    In this work we investigate a model for the early Universe in a Bianchi type-I metric, where the sources of the gravitational field are a fermionic and a bosonic field, interacting through a Yukawa potential, following the standard model of elementary particles. It is shown that the fermionic field has a negative pressure, while the boson has a small positive pressure. The fermionic field is the responsible for an accelerated regime at early times, but since the total pressure tends to zero for large times, a transition to a decelerated regime occurs. Here the Yukawa potential answers for the duration of the accelerated regime, since by decreasing the value of its coupling constant the transition accelerated-decelerated occurs in later times. The isotropization which occurs for late times is due to the presence of the fermionic field as one of the sources of the gravitational field.

  18. Contaminant Interactions and Biological Effects of Single-walled Carbon Nanotubes in a Benthic Estuarine System

    Science.gov (United States)

    Parks, Ashley Nicole

    The fate, bioavailability, bioaccumulation and toxicity of single-walled carbon nanotubes (SWNT) have not been extensively studied to date. Pristine SWNT are highly hydrophobic and have been shown to strongly associate with natural particulate matter in aquatic environments. In light of this, I have focused my research to examine the influence of sediment and food exposure routes on bioavailability, bioaccumulation, and toxicity of structurally diverse SWNT in several ecologically-important marine invertebrate species. No significant mortality was observed in any organism at concentrations up to 1000 mg/kg. Evidence of biouptake after ingestion was observed for pristine semiconducting SWNT using NIRF spectroscopy and for oxidized 14C-SWNT using liquid scintillation counting. After a 24 hour depuration period, the pristine semiconducting SWNT were eliminated from organisms to below the method detection limit (5 microg/mL), and the 14C-SWNT body burden was decreased by an order of magnitude to a bioaccumulation factor (BAF) of invertebrates. Overall, the SWNT were not bioavailable and appear to associate with the sediment. In addition to investigating the toxicity and bioaccumulation of SWNT as an independent toxicant, it is important to consider how they will interact with other contaminants in the environment (i.e., increase or decrease toxicity and bioaccumulation of co-contaminants, alter the environmental transport of co-contaminants, induce degradation of co-contaminants, etc.). I wanted to investigate the effects of SWNT on a complex mixture of contaminants already present in a natural system. New Bedford Harbor (NBH) sediment, which is contaminated with polychlorinated biphenyls (PCBs), was amended with pristine SWNT to determine if the presence of SWNT would mitigate the toxicity and bioaccumulation of the PCBs in deposit-feeding invertebrates. A dilution series of the NBH sediment was created using uncontaminated Long Island Sound (LIS) sediment to test 25

  19. Thermo-chemical and biological conversion potential of various biomass feedstocks to ethanol

    Science.gov (United States)

    The goal of this study is to evaluate the potential and the economy of producing ethanol from gasification-fermentation of various biomass feedstocks. The biomass feedstocks include winter cover crops (wheat, rye, clover, hairy betch), summer cover crop (sunhemp), chicken litter, and woody biomass. ...

  20. Biological productivity and potential resources of the exclusive economic zone (EEZ) of India

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, S.C.

    degree square was calculated from the production data. The potential fishery resources including demersal fishery of the entire EEZ of India worked out to be 3.45 million tones yr sup(-1). Since the annual fishery production is around 2.7 million tones...

  1. A C-code for the double folding interaction potential of two spherical nuclei

    Science.gov (United States)

    Gontchar, I. I.; Chushnyakova, M. V.

    2010-01-01

    We present a C-code designed to obtain the nucleus-nucleus potential by using the double folding model (DFM) and in particular to find the Coulomb barrier. The program calculates the nucleus-nucleus potential as a function of the distance between the centers of mass of colliding nuclei. The most important output parameters are the Coulomb barrier energy and the radius. Since many researchers use a Woods-Saxon profile for the nuclear term of the potential we provide an option in our code for fitting the DFM potential by such a profile. Program summaryProgram title: DFMSPH Catalogue identifier: AEFH_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEFH_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 5929 No. of bytes in distributed program, including test data, etc.: 115 740 Distribution format: tar.gz Programming language: C Computer: PC Operating system: Windows XP (with the GCC-compiler version 2) RAM: Below 10 Mbyte Classification: 17.9 Nature of problem: The code calculates in a semimicroscopic way the bare interaction potential between two colliding spherical nuclei as a function of the center of mass distance. The height and the position of the Coulomb barrier are found. The calculated potential is approximated by a conventional Woods-Saxon profile near the barrier. Dependence of the barrier parameters upon the characteristics of the effective NN forces (like, e.g. the range of the exchange part of the nuclear term) can be investigated. Solution method: The nucleus-nucleus potential is calculated using the double folding model with the Coulomb and the effective M3Y NN interactions. For the direct parts of the Coulomb and the nuclear terms, the Fourier transform method is used. In order to calculate the exchange parts the density matrix expansion method

  2. Interaction of landscape varibles on the potential geographical distribution of parrots in the Yucatan Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Plasencia–Vázquez, A. H.

    2014-12-01

    Full Text Available The loss, degradation, and fragmentation of forested areas are endangering parrot populations. In this study, we determined the influence of fragmentation in relation to vegetation cover, land use, and spatial configuration of fragments on the potential geographical distribution patterns of parrots in the Yucatan Peninsula, Mexico. We used the potential geographical distribution for eight parrot species, considering the recently published maps obtained with the maximum entropy algorithm, and we incorporated the probability distribution for each species. We calculated 71 metrics/variables that evaluate forest fragmentation, spatial configuration of fragments, the ratio occupied by vegetation, and the land use in 100 plots of approximately 29 km², randomly distributed within the presence and absence areas predicted for each species. We also considered the relationship between environmental variables and the distribution probability of species. We used a partial least squares regression to explore patterns between the variables used and the potential distribution models. None of the environmental variables analyzed alone determined the presence/absence or the probability distribution of parrots in the Peninsula. We found that for the eight species, either due to the presence/absence or the probability distribution, the most important explanatory variables were the interaction among three variables, particularly the interactions among the total forest area, the total edge, and the tropical semi–evergreen medium– height forest. Habitat fragmentation influenced the potential geographical distribution of these species in terms of the characteristics of other environmental factors that are expressed together with the geographical division, such as the different vegetation cover ratio and land uses in deforested areas.

  3. An apparatus for conducting physical, chemical, or biological interaction between gases and solid particles

    DEFF Research Database (Denmark)

    2013-01-01

    The invention provides an apparatus for conducting interaction between gases and solid particles. The apparatus has a vertical hollow shaft with a vertical row of constrictions formed internally and defining a series of intercommunicating chambers in the shaft for guiding the gas and particles e.......g. in counter current to effect interaction there between, e.g. for transferring thermal energy. To enable redesign of the apparatus and to enable an improved match between need for capacity and size of the apparatus, the invention provides an apparatus where the shaft comprises a stack of separate...

  4. Cellular Interactions and Biological Responses to Titanium Dioxide Nanoparticles in HepG2 and BEAS-2B Cells: Role of Cell Culture Media

    Science.gov (United States)

    ABSTRACT We have shown previously that the composition of the biological medium used in vitro can affect the cellular interaction and biological response of titanium dioxide nanoparticles (nano-TiO2) in human lung epithelial cells. However, it is unclear if these effects are co...

  5. Isolation and characterization of soil Streptomyces species as potential biological control agents against fungal plant pathogens.

    Science.gov (United States)

    Evangelista-Martínez, Zahaed

    2014-05-01

    The use of antagonist microorganisms against fungal plant pathogens is an attractive and ecologically alternative to the use of chemical pesticides. Streptomyces are beneficial soil bacteria and potential candidates for biocontrol agents. This study reports the isolation, characterization and antagonist activity of soil streptomycetes from the Los Petenes Biosphere Reserve, a Natural protected area in Campeche, Mexico. The results showed morphological, physiological and biochemical characterization of six actinomycetes and their inhibitory activity against Curvularia sp., Aspergillus niger, Helminthosporium sp. and Fusarium sp. One isolate, identified as Streptomyces sp. CACIS-1.16CA showed the potential to inhibit additional pathogens as Alternaria sp., Phytophthora capsici, Colletotrichum sp. and Rhizoctonia sp. with percentages ranging from 47 to 90 %. This study identified a streptomycete strain with a broad antagonist activity that could be used for biocontrol of plant pathogenic fungi. PMID:24310522

  6. The Potential of the South American Leaf Blight as a Biological Agent

    Directory of Open Access Journals (Sweden)

    Oghenekome Onokpise

    2012-11-01

    Full Text Available When asked by the Department of Homeland Security to create potential terrorism scenarios, even “Out of the Box Thinkers” initially failed to come up with the following scenario. Oil tankers, refineries, nuclear plants, etc., are obvious potential terrorists’ targets, and adequate measures are being taken to protect them. However, what if the target were to be a non-food commodity product, such as natural rubber tree plantations located in places as remote as southeast Asian countries like Thailand or Indonesia? Would it be of concern? At first thought “maybe not”, but think again. What could the release of a deadly microorganism (fungus/virus/bacteria in a rubber tree plantation in Indonesia, Malaysia or Thailand possibly mean to you or the world economy?

  7. Spatial representation in the social interaction potential metric: an analysis of scale and parameter sensitivity

    Science.gov (United States)

    Li, Xiao; Farber, Steven

    2016-10-01

    The social interaction potential (SIP) metric measures urban structural constraints on social interaction opportunities of a metropolitan region based on the time geographic concept of joint accessibility. Previous implementations of the metric used an interaction surface based on census tracts and the locations of their centroids. This has been shown to be a shortcoming, as the metric strongly depends on the scale of the zoning system in the region, making it difficult to compare the SIP metric between metropolitan regions. This research explores the role of spatial representation in the SIP metric and identifies a suitable grid-based representation that allows for comparison between regions while retaining cost-effectiveness with respect to computational burden. We also report on findings from an extensive sensitivity analysis investigating the SIP metric's input parameters such as a travel flow congestion factor and the length of the allowable time budget for social activities. The results provide new insights on the role of the modifiable areal unit problem in the computation of time geographic measures of accessibility.

  8. Cubic-quintic long-range interactions with double well potentials

    Science.gov (United States)

    Tsilifis, Panagiotis A.; Kevrekidis, Panayotis G.; Rothos, Vassilis M.

    2014-01-01

    In the present work, we examine the combined effects of cubic and quintic terms of the long-range type in the dynamics of a double well potential. Employing a two-mode approximation, we systematically develop two cubic-quintic ordinary differential equations and assess the contributions of the long-range interactions in each of the relevant prefactors, gauging how to simplify the ensuing dynamical system. Finally, we obtain a reduced canonical description for the conjugate variables of relative population imbalance and relative phase between the two wells and proceed to a dynamical systems analysis of the resulting pair of ordinary differential equations. While in the case of cubic and quintic interactions of the same kind (e.g. both attractive or both repulsive), only a symmetry-breaking bifurcation can be identified, a remarkable effect that emerges e.g. in the setting of repulsive cubic but attractive quintic interactions is a ‘symmetry-restoring’ bifurcation. Namely, in addition to the supercritical pitchfork that leads to a spontaneous symmetry breaking of the antisymmetric state, there is a subcritical pitchfork that eventually reunites the asymmetric daughter branch with the antisymmetric parent one. The relevant bifurcations, the stability of the branches and their dynamical implications are examined both in the reduced (ODE) and in the full (PDE) setting. The model is argued to be of physical relevance, especially so in the context of optical thermal media.

  9. Biodegradation and detoxification potential of rotating biological contactor (RBC) with Irpex lacteus for remediation of dye-containing wastewater.

    Science.gov (United States)

    Malachova, Katerina; Rybkova, Zuzana; Sezimova, Hana; Cerven, Jiri; Novotny, Cenek

    2013-12-01

    Use of fungal organisms in rotating biological contactors (RBC) for bioremediation of liquid industrial wastes has so far been limited in spite of their significant biodegradation potential. The purpose was to investigate the power of RBC using Irpex lacteus for decolorization and detoxification of industrial dyes and dyeing textile liquors. Recalcitrant dye Methylene Blue (150 mg L(-1)) was decolorized within 70 days, its mutagenicity removed, and the biological toxicity decreased more than 10-fold. I. lacteus biofilm in the RBC completely decolorized within 26 and 47 days dyeing liquors containing disperse or reactive dyes adjusted to pH4.5 and 5-fold diluted with the growth medium, respectively. Their respective biological toxicity values were reduced 10- to 10(4)-fold in dependence of the test used. A battery of toxicity tests comprising Vibrio fisheri, Lemna minor and Sinapis alba was efficient to monitor the toxicity of textile dyes and wastewaters. Strong decolorization and detoxification power of RBC using I. lacteus biofilms was demonstrated.

  10. Quality of Life Theory II. Quality of Life as the Realization of Life Potential: A Biological Theory of Human Being

    Directory of Open Access Journals (Sweden)

    Soren Ventegodt

    2003-01-01

    Full Text Available This review presents one of the eight theories of the quality of life (QOL used for making the SEQOL (self-evaluation of quality of life questionnaire or the quality of life as realizing life potential. This theory is strongly inspired by Maslow and the review furthermore serves as an example on how to fulfill the demand for an overall theory of life (or philosophy of life, which we believe is necessary for global and generic quality-of-life research.Whereas traditional medical science has often been inspired by mechanical models in its attempts to understand human beings, this theory takes an explicitly biological starting point. The purpose is to take a close view of life as a unique entity, which mechanical models are unable to do. This means that things considered to be beyond the individual's purely biological nature, notably the quality of life, meaning in life, and aspirations in life, are included under this wider, biological treatise. Our interpretation of the nature of all living matter is intended as an alternative to medical mechanism, which dates back to the beginning of the 20th century. New ideas such as the notions of the human being as nestled in an evolutionary and ecological context, the spontaneous tendency of self-organizing systems for realization and concord, and the central role of consciousness in interpreting, planning, and expressing human reality are unavoidable today in attempts to scientifically understand all living matter, including human life.

  11. Phytotoxic Potential and Biological Activity of Three Synthetic Coumarin Derivatives as New Natural-Like Herbicides

    OpenAIRE

    Fabrizio Araniti; Raffaella Mancuso; Antonio Lupini; Salvatore V. Giofrè; Francesco Sunseri; Bartolo Gabriele; Maria Rosa Abenavoli

    2015-01-01

    Coumarin is a natural compound well known for its phytotoxic potential. In the search for new herbicidal compounds to manage weeds, three synthetic derivatives bearing the coumarin scaffold (1–3), synthesized by a carbonylative organometallic approach, were in vitro assayed on germination and root growth of two noxious weeds, Amaranthus retroflexus and Echinochloa crus-galli. Moreover, the synthetic coumarins 1–3 were also in vitro assayed on seedlings growth of the model species Arabidopsis ...

  12. The virome: a missing component of biological interaction networks in health and disease.

    Science.gov (United States)

    Handley, Scott A

    2016-01-01

    Host-associated viral populations, viromes, have been understudied relative to their contribution to human physiology. Viruses interact with host gene networks, influencing both health and disease. Analysis of host gene networks in the absence of virome analysis risks missing important network information. PMID:27037032

  13. Interaction of Biologically Active Molecules with Sulfur-modified Gold Surface

    Institute of Scientific and Technical Information of China (English)

    DING Xue-feng; YANG Gui-fu; WANG Xiao; WANG Zi-chen; LIN Hai-bo

    2007-01-01

    The immobilization of cytochrome c or horseradish peroxidase at the sulfur-modified gold electrode exhibits a ra-pid electron transfer behavior because of its specific orientation on the electrode surface and the interaction between cytochrome c or horseradish peroxidase and sulfur-modified on the surface of the Au electrode.

  14. Visualizing Biological Data in Museums: Visitor Learning with an Interactive Tree of Life Exhibit

    Science.gov (United States)

    Horn, Michael S.; Phillips, Brenda C.; Evans, Evelyn Margaret; Block, Florian; Diamond, Judy; Shen, Chia

    2016-01-01

    In this study, we investigate museum visitor learning and engagement at an interactive visualization of an evolutionary tree of life consisting of over 70,000 species. The study was conducted at two natural history museums where visitors collaboratively explored the tree of life using direct touch gestures on a multi-touch tabletop display. In the…

  15. Anaerobic Fungi: A Potential Source of Biological H2 in the Oceanic Crust

    Science.gov (United States)

    Ivarsson, Magnus; Schnürer, Anna; Bengtson, Stefan; Neubeck, Anna

    2016-01-01

    The recent recognition of fungi in the oceanic igneous crust challenges the understanding of this environment as being exclusively prokaryotic and forces reconsiderations of the ecology of the deep biosphere. Anoxic provinces in the igneous crust are abundant and increase with age and depth of the crust. The presence of anaerobic fungi in deep-sea sediments and on the seafloor introduces a type of organism with attributes of geobiological significance not previously accounted for. Anaerobic fungi are best known from the rumen of herbivores where they produce molecular hydrogen, which in turn stimulates the growth of methanogens. The symbiotic cooperation between anaerobic fungi and methanogens in the rumen enhance the metabolic rate and growth of both. Methanogens and other hydrogen-consuming anaerobic archaea are known from subseafloor basalt; however, the abiotic production of hydrogen is questioned to be sufficient to support such communities. Alternatively, biologically produced hydrogen could serve as a continuous source. Here, we propose anaerobic fungi as a source of bioavailable hydrogen in the oceanic crust, and a close interplay between anaerobic fungi and hydrogen-driven prokaryotes. PMID:27433154

  16. Potential nitrosamine formation and its prevention during biological denitrification of red beet juice.

    Science.gov (United States)

    Kolb, E; Haug, M; Janzowski, C; Vetter, A; Eisenbrand, G

    1997-02-01

    High nitrate intake has been shown to result in an increased risk of endogenous formation of N-nitroso compounds. Certain vegetables and vegetable juices contain high concentrations of nitrate. Biological denitrification using strains of Paracoccus denitrificans (P.d.) has been proposed as effective means to reduce nitrate contents in such vegetable juices. During this bacterial denitrification process, substantial nitrite concentrations are transiently formed. This study investigated whether N-nitrosation reactions might occur. The easily nitrosatable amine morpholine was added to red beet juice at high concentration (100 ppm) during denitrification 10 different batches of red beet juice served as raw material. Each batch was submitted to denitrification in the presence and absence of ascorbic acid. In the absence of ascorbic acid, formation of N-nitrosomorpholine (NMOR) was observed in the low ppb range (0.5-8 ppb). Addition of ascorbic acid (500 mg/litre) inhibited the formation of NMOR, except for those instances where the pH was less than 6 and/or nitrate turnover was low (high rates of nitrate turnover (> 200 mg NO3-/litre/hr), nitrosamine formation can reliably be prevented by ascorbic acid. The results show that bacterial denitrification of red beet juice high in nitrate can be accomplished without the risk of nitrosamine formation. PMID:9146735

  17. Sulfated polysaccharides from Loligo vulgaris skin: potential biological activities and partial purification.

    Science.gov (United States)

    Abdelmalek, Baha Eddine; Sila, Assaâd; Krichen, Fatma; Karoud, Wafa; Martinez-Alvarez, Oscar; Ellouz-Chaabouni, Semia; Ayadi, Mohamed Ali; Bougatef, Ali

    2015-01-01

    The characteristics, biological properties, and purification of sulfated polysaccharides extracted from squid (Loligo vulgaris) skin were investigated. Their chemical and physical characteristics were determined using X-ray diffraction and infrared spectroscopic analysis. Sulfated polysaccharides from squid skin (SPSS) contained 85.06% sugar, 2.54% protein, 1.87% ash, 8.07% sulfate, and 1.72% uronic acid. The antioxidant properties of SPSS were investigated based on DPPH radical-scavenging capacity (IC50 = 19.42 mg mL(-1)), hydrogen peroxide-scavenging activity (IC50 = 0.91 mg mL(-1)), and β-carotene bleaching inhibition (IC50 = 2.79 mg mL(-1)) assays. ACE-inhibitory activity of SPSS was also investigated (IC50 = 0.14 mg mL(-1)). Further antimicrobial activity assays indicated that SPSS exhibited marked inhibitory activity against the bacterial and fungal strains tested. Those polysaccharides did not display hemolytic activity towards bovine erythrocytes. Fractionation by DEAE-cellulose column chromatography showed three major absorbance peaks. Results of this study suggest that sulfated polysaccharides from squid skin are attractive sources of polysaccharides and promising candidates for future application as dietary ingredients.

  18. Anaerobic fungi: a potential source of biological H2 in the oceanic crust

    Directory of Open Access Journals (Sweden)

    Magnus eIvarsson

    2016-05-01

    Full Text Available The recent recognition of fungi in the oceanic igneous crust challenges the understanding of this environment as being exclusively prokaryotic and forces reconsiderations of the ecology of the deep biosphere. Anoxic provinces in the igneous crust are abundant and increase with age and depth of the crust. The presence of anaerobic fungi in deep-sea sediments and on the seafloor introduces a type of organism with attributes of geobiological significance not previously accounted for. Anaerobic fungi are best known from the rumen of herbivores where they produce molecular hydrogen, which in turn stimulates the growth of methanogens. The symbiotic cooperation between anaerobic fungi and methanogens in the rumen enhance the metabolic rate and growth of both. Methanogens and other hydrogen-consuming anaerobic archaea are known from subseafloor basalt; however, the abiotic production of hydrogen is questioned to be sufficient to support such communities. Alternatively, biologically produced hydrogen could serve as a continuous source. Here we propose anaerobic fungi as a source of bioavailable hydrogen in the oceanic crust, and a close interplay between anaerobic fungi and hydrogen-driven prokaryotes.

  19. Melatonin and its potential biological functions in the fruits of sweet cherry.

    Science.gov (United States)

    Zhao, Yu; Tan, Dun-Xian; Lei, Qiong; Chen, Hao; Wang, Lin; Li, Qing-tian; Gao, Yinan; Kong, Jin

    2013-08-01

    Melatonin is a well-known molecule which possesses many beneficial effects on human health. Many agriculture products provide natural melatonin in the diet. Cherry is one such fruit as they are rich in melatonin. In order to understand the biological roles of melatonin in cherry fruit, melatonin synthesis and its changes over 24 hr period were systematically monitored both during their development and in the ripe cherries in two cultivars, 'Hongdeng' (Prunus avium L. cv. Hongdeng) and 'Rainier' (Prunus avium L. cv. Rainier). It was found that both darkness and oxidative stress induced melatonin synthesis, which led to dual melatonin synthetic peaks during a 24 hr period. The high levels of malondialdehyde induced by high temperature and high intensity light exposure were directly related to up-regulated melatonin production. A primary function of melatonin in cherry fruits is speculated to be as an antioxidant to protect the cherry from the oxidative stress. Importantly, plant tryptophan decaboxylase gene (PaTDC) was identified in cherry fruits. Our data shows that PaTDC expression is positively related to the melatonin production in the cherry. This provides additional information to suggest that tryptophan decaboxylase is a rate-limiting enzyme of melatonin synthesis in plants. PMID:23480341

  20. Novel pyrazolopyridine derivatives as potential angiogenesis inhibitors: Synthesis, biological evaluation and transcriptome-based mechanistic analysis.

    Science.gov (United States)

    Michailidou, Maria; Giannouli, Vassiliki; Kotsikoris, Vasilios; Papadodima, Olga; Kontogianni, Georgia; Kostakis, Ioannis K; Lougiakis, Nikolaos; Chatziioannou, Aristotelis; Kolisis, Fragiskos N; Marakos, Panagiotis; Pouli, Nicole; Loutrari, Heleni

    2016-10-01

    Modified purine derivatives exemplified by pyrazolopyrimidines have emerged as highly selective inhibitors of several angiogenic receptor tyrosine kinases. Herein, we designed and synthesized a new series of substituted pyrazolopyridines and explored their ability to influence crucial pro-angiogenic attributes of endothelial cells. Four of the synthesized compounds, possessing analogous substitution pattern, were found able to inhibit at low micromolar concentrations endothelial cell proliferation, migration and differentiation, constitutively or in response to Vascular Endothelial Growth Factor (VEGF) and to attenuate VEGF-induced phosphorylation of VEGF receptor-2 and downstream kinases AKT and ERK1/2. Administration of effective compounds in mice delayed the growth of syngeneic Lewis lung carcinoma transplants and reduced tumor microvessel density, without causing toxicity. Genome-wide microarray and gene ontology analyses of treated endothelial cells revealed derivative 18c as the most efficient modulator of gene expression and "mitotic cell cycle/cell division" along with "cholesterol biosynthesis" as the most significantly altered biological processes. PMID:27240270