WorldWideScience

Sample records for biological resistance

  1. Biological improvement of radiation resistance

    Energy Technology Data Exchange (ETDEWEB)

    Chun, K. J.; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J

    2000-08-01

    To investigate the mechanisms of gene action related to the radiation resistance in microorganisms could be essentially helpful for the development of radiation protectants and hormeric effects of low dose radiation. This book described isolation of radiation-resistant microorganisms, induction of radiation-resistant and functionally improved mutants by gamma-ray radiation, cloning and analysis of the radiation resistance related genes and analysis of the expressed proteins of the radiation resistant related genes.

  2. Biological improvement of radiation resistance

    International Nuclear Information System (INIS)

    To investigate the mechanisms of gene action related to the radiation resistance in microorganisms could be essentially helpful for the development of radiation protectants and hormeric effects of low dose radiation. This book described isolation of radiation-resistant microorganisms, induction of radiation-resistant and functionally improved mutants by gamma-ray radiation, cloning and analysis of the radiation resistance related genes and analysis of the expressed proteins of the radiation resistant related genes

  3. Adaptive resistance to antibiotics in bacteria: a systems biology perspective.

    Science.gov (United States)

    Sandoval-Motta, Santiago; Aldana, Maximino

    2016-05-01

    Despite all the major breakthroughs in antibiotic development and treatment procedures, there is still no long-term solution to the bacterial antibiotic resistance problem. Among all the known types of resistance, adaptive resistance (AdR) is particularly inconvenient. This phenotype is known to emerge as a consequence of concentration gradients, as well as contact with subinhibitory concentrations of antibiotics, both known to occur in human patients and livestock. Moreover, AdR has been repeatedly correlated with the appearance of multidrug resistance, although the biological processes behind its emergence and evolution are not well understood. Epigenetic inheritance, population structure and heterogeneity, high mutation rates, gene amplification, efflux pumps, and biofilm formation have all been reported as possible explanations for its development. Nonetheless, these concepts taken independently have not been sufficient to prevent AdR's fast emergence or to predict its low stability. New strains of resistant pathogens continue to appear, and none of the new approaches used to kill them (mixed antibiotics, sequential treatments, and efflux inhibitors) are completely efficient. With the advent of systems biology and its toolsets, integrative models that combine experimentally known features with computational simulations have significantly improved our understanding of the emergence and evolution of the adaptive-resistant phenotype. Apart from outlining these findings, we propose that one of the main cornerstones of AdR in bacteria, is the conjunction of two types of mechanisms: one rapidly responding to transient environmental challenges but not very efficient, and another much more effective and specific, but developing on longer time scales. WIREs Syst Biol Med 2016, 8:253-267. doi: 10.1002/wsbm.1335 For further resources related to this article, please visit the WIREs website. PMID:27103502

  4. Adaptive resistance to antibiotics in bacteria: a systems biology perspective.

    Science.gov (United States)

    Sandoval-Motta, Santiago; Aldana, Maximino

    2016-05-01

    Despite all the major breakthroughs in antibiotic development and treatment procedures, there is still no long-term solution to the bacterial antibiotic resistance problem. Among all the known types of resistance, adaptive resistance (AdR) is particularly inconvenient. This phenotype is known to emerge as a consequence of concentration gradients, as well as contact with subinhibitory concentrations of antibiotics, both known to occur in human patients and livestock. Moreover, AdR has been repeatedly correlated with the appearance of multidrug resistance, although the biological processes behind its emergence and evolution are not well understood. Epigenetic inheritance, population structure and heterogeneity, high mutation rates, gene amplification, efflux pumps, and biofilm formation have all been reported as possible explanations for its development. Nonetheless, these concepts taken independently have not been sufficient to prevent AdR's fast emergence or to predict its low stability. New strains of resistant pathogens continue to appear, and none of the new approaches used to kill them (mixed antibiotics, sequential treatments, and efflux inhibitors) are completely efficient. With the advent of systems biology and its toolsets, integrative models that combine experimentally known features with computational simulations have significantly improved our understanding of the emergence and evolution of the adaptive-resistant phenotype. Apart from outlining these findings, we propose that one of the main cornerstones of AdR in bacteria, is the conjunction of two types of mechanisms: one rapidly responding to transient environmental challenges but not very efficient, and another much more effective and specific, but developing on longer time scales. WIREs Syst Biol Med 2016, 8:253-267. doi: 10.1002/wsbm.1335 For further resources related to this article, please visit the WIREs website.

  5. Bridging Physics and Biology Using Resistance and Axons

    Science.gov (United States)

    Dyer, Joshua M.

    2014-11-01

    When teaching physics, it is often difficult to get biology-oriented students to see the relevance of physics.1 A complaint often heard is that biology students are required to take physics for the Medical College Admission Test (MCAT) as part of a "weeding out" process, but that they don't feel like they need physics for biology. Despite this impression held by students, there have been calls for better physics education for future physicians and life scientists.2,3 Research is being performed to improve physics classes and labs by linking topics in biology and physics.4,5 Described here is a laboratory experiment covering the topics of resistance of materials and circuits/Kirchhoff's laws in a biology context with their direct application to neurons, axons, and electrical impulse transmission within animals. This experiment will also demonstrate the mechanism believed to cause multiple sclerosis. The apparatus was designed with low-cost and readily available materials in mind.

  6. Joining the club: Conforming to and resisting biology in practice

    Science.gov (United States)

    Buxton, Cory Alexander

    2000-10-01

    This study explores how science and scientists were produced and reproduced within the setting of a university biology department. It builds upon recent work in anthropology of education and feminist science studies. My purpose was to look at both the contextual and constitutive values of science as they were negotiated and played out in the training of scientists in a setting where: (1) women were well represented in leadership positions; and (2) "mainstream" science was being both taught and practiced. Findings included the organization of a status hierarchy within the department, the meanings of science and scientists that students constructed within the social spaces they occupied, examples of individual resistance to certain norms of biology practice, and examples of institutional opposition to that resistance. There was some evidence that the unusually high representation of women in positions of leadership in the biology department did result in changes in both the contextual and constitutive values of how science was conceptualized, practiced and taught in this setting. Contextually, social spaces controlled by women were likely to emphasize: (1) teamwork bringing together participants with varied backgrounds and perspectives; (2) flexible and collaborative use of physical space; and (3) willingness to do work for which they went unacknowledged or to share rewards equally even when the work distribution was not equitable. Constitutively, these social spaces were prone to: (1) interdisciplinary synthesis and comprehensive approaches; (2) the study of topics that reconsidered beliefs about gender roles in plant and animal reproduction; (3) work that would be slower and take longer to produce (and publish) but might make a large contribution (be a high quality product) eventually; and (4) an awareness by women that their practices were different in some ways than the practices of their male colleagues.

  7. Antimicrobial resistance and biological governance: explanations for policy failure.

    Science.gov (United States)

    Wallinga, D; Rayner, G; Lang, T

    2015-10-01

    The paper reviews the state of policy on antimicrobial use and the growth of antimicrobial resistance (AMR). AMR was anticipated at the time of the first use of antibiotics by their originators. For decades, reports and scientific papers have expressed concern about AMR at global and national policy levels, yet the problem, first exposed a half-century ago, worsened. The paper considers the explanations for this policy failure and the state of arguments about ways forward. These include: a deficit of economic incentivisation; complex interventions in behavioural dynamics; joint and separate shifts in medical and animal health regimes; consumerism; belief in technology; and a narrative that in a 'war on bugs' nature can be beaten by human ingenuity. The paper suggests that these narratives underplay the biological realities of the human-animal-biosphere being in constant flux, an understanding which requires an ecological public health analysis of AMR policy development and failure. The paper suggests that effective policy change requires simultaneous actions across policy levels. No single solution is possible, since AMR is the result of long-term human intervention which has accelerated certain trends in the evolution of a microbial ecosystem shared by humans, animals and other biological organisms inhabiting that ecosystem. Viewing the AMR crisis today through an ecological public health lens has the advantage of reuniting the social-ecological and bio-ecological perspectives which have been separated within public health. PMID:26454427

  8. Systems biology of cisplatin resistance: past, present and future.

    Science.gov (United States)

    Galluzzi, L; Vitale, I; Michels, J; Brenner, C; Szabadkai, G; Harel-Bellan, A; Castedo, M; Kroemer, G

    2014-01-01

    The platinum derivative cis-diamminedichloroplatinum(II), best known as cisplatin, is currently employed for the clinical management of patients affected by testicular, ovarian, head and neck, colorectal, bladder and lung cancers. For a long time, the antineoplastic effects of cisplatin have been fully ascribed to its ability to generate unrepairable DNA lesions, hence inducing either a permanent proliferative arrest known as cellular senescence or the mitochondrial pathway of apoptosis. Accumulating evidence now suggests that the cytostatic and cytotoxic activity of cisplatin involves both a nuclear and a cytoplasmic component. Despite the unresolved issues regarding its mechanism of action, the administration of cisplatin is generally associated with high rates of clinical responses. However, in the vast majority of cases, malignant cells exposed to cisplatin activate a multipronged adaptive response that renders them less susceptible to the antiproliferative and cytotoxic effects of the drug, and eventually resume proliferation. Thus, a large fraction of cisplatin-treated patients is destined to experience therapeutic failure and tumor recurrence. Throughout the last four decades great efforts have been devoted to the characterization of the molecular mechanisms whereby neoplastic cells progressively lose their sensitivity to cisplatin. The advent of high-content and high-throughput screening technologies has accelerated the discovery of cell-intrinsic and cell-extrinsic pathways that may be targeted to prevent or reverse cisplatin resistance in cancer patients. Still, the multifactorial and redundant nature of this phenomenon poses a significant barrier against the identification of effective chemosensitization strategies. Here, we discuss recent systems biology studies aimed at deconvoluting the complex circuitries that underpin cisplatin resistance, and how their findings might drive the development of rational approaches to tackle this clinically relevant

  9. Bridging Physics and Biology Using Resistance and Axons

    Science.gov (United States)

    Dyer, Joshua M.

    2014-01-01

    When teaching physics, it is often difficult to get biology-oriented students to see the relevance of physics. A complaint often heard is that biology students are required to take physics for the Medical College Admission Test (MCAT) as part of a "weeding out" process, but that they don't feel like they need physics for biology.…

  10. Translational research in ovarian carcinoma : cell biological aspects of drug resistance and tumor aggressiveness

    NARCIS (Netherlands)

    Zee, Ate Gerard Jan van der

    1994-01-01

    In this thesis diverse cell biological features that in cultured (ovarian) tumor cells have been linked to drug resistance and/or tumor aggressiveness are studied in tumor specimens of epithelial ovarian carcinomas.

  11. Cell biological mechanisms of multidrug resistance in tumors.

    OpenAIRE

    Simon, S. M.; Schindler, M

    1994-01-01

    Multidrug resistance (MDR) is a generic term for the variety of strategies tumor cells use to evade the cytotoxic effects of anticancer drugs. MDR is characterized by a decreased sensitivity of tumor cells not only to the drug employed for chemotherapy but also to a broad spectrum of drugs with neither obvious structural homology nor common targets. This pleiotropic resistance is one of the major obstacles to the successful treatment of tumors. MDR may result from structural or functional cha...

  12. Leaf Rust of Wheat: Pathogen Biology, Variation and Host Resistance

    Directory of Open Access Journals (Sweden)

    James Kolmer

    2013-01-01

    Full Text Available Rusts are important pathogens of angiosperms and gymnosperms including cereal crops and forest trees. With respect to cereals, rust fungi are among the most important pathogens. Cereal rusts are heteroecious and macrocyclic requiring two taxonomically unrelated hosts to complete a five spore stage life cycle. Cereal rust fungi are highly variable for virulence and molecular polymorphism. Leaf rust, caused by Puccinia triticina is the most common rust of wheat on a worldwide basis. Many different races of P. triticina that vary for virulence to leaf rust resistance genes in wheat differential lines are found annually in the US. Molecular markers have been used to characterize rust populations in the US and worldwide. Highly virulent races of P. triticina are selected by leaf rust resistance genes in the soft red winter wheat, hard red winter wheat and hard red spring wheat cultivars that are grown in different regions of the US. Cultivars that only have race-specific leaf rust resistance genes that are effective in seedling plants lose their effective resistance and become susceptible within a few years of release. Cultivars with combinations of race non-specific resistance genes have remained resistant over a period of years even though races of the leaf rust population have changed constantly.

  13. Research of resisting of the biological active point for constant and alternative current

    Directory of Open Access Journals (Sweden)

    S. N. Peregudov

    2008-05-01

    Full Text Available Is conducted research of resistance of biologically active point (BAT on a direct and variable current. Research results are presented. The estimation of intercommunication between resistance of skin and by an electromagnetic radiation in BAT is done. Is shown possibility of the use of experimental information for diagnostics of the state of human to the organism.

  14. Quantitative phenotyping of powdery mildew resistance in grapevine reveals differences in host resistance biology

    Science.gov (United States)

    The recent demonstration of race-specific resistance to Erysiphe necator has encouraged grapevine breeders to identify and introgress quantitative resistance genes exhibiting complementary mechanisms. In 2012, we established a phenotyping center (VitisGenPM) for detailed evaluation of resistance to...

  15. Diversity and biology of heat-resistant fungi

    NARCIS (Netherlands)

    Houbraken, J.; Dijksterhuis, J.; Samson, R.A.; Wong, Hin-Chung

    2012-01-01

    Heat-resistant fungi survive high temperatures (75°C or more for at least 30 min). For food microbiology, these fungi are of interest because of spoilage of canned and pasteurized food products, and cause damage for millions of dollars in the fruit-juice and beverage branch. Many studies have been c

  16. Cell Biological Mechanisms of Multidrug Resistance in Tumors

    Science.gov (United States)

    Simon, Sanford M.; Schindler, Melvin

    1994-04-01

    Multidrug resistance (MDR) is a generic term for the variety of strategies tumor cells use to evade the cytotoxic effects of anticancer drugs. MDR is characterized by a decreased sensitivity of tumor cells not only to the drug employed for chemotherapy but also to a broad spectrum of drugs with neither obvious structural homology nor common targets. This pleotropic resistance is one of the major obstacles to the successful treatment of tumors. MDR may result from structural or functional changes at the plasma membrane or within the cytoplasm, cellular compartments, or nucleus. Molecular mechanisms of MDR are discussed in terms of modifications in detoxification and DNA repair pathways, changes in cellular sites of drug sequestration, decreases in drug-target affinity, synthesis of specific drug inhibitors within cells, altered or inappropriate targeting of proteins, and accelerated removal or secretion of drugs.

  17. Fabrication Effects on Polysilicon-based Micro cantilever Piezo resistivity for Biological Sensing Application

    International Nuclear Information System (INIS)

    In principle, adsorption of biological molecules on a functionalized surface of a micro fabricated cantilever will cause a surface stress and consequently the cantilever bending. In this work, four different type of polysilicon-based piezo resistive micro cantilever sensors were designed to increase the sensitivity of the micro cantilevers sensor because the forces involved is very small. The design and optimization was performed by using finite element analysis to maximize the relative resistance changes of the piezo resistors as a function of the cantilever vertical displacements. The resistivity of the piezo resistivity micro cantilevers was analyzed before and after dicing process. The maximum resistance changes were systematically investigated by varying the piezo resistor length. The results show that although the thickness of piezo resistor was the same at 0.5 μm the resistance value was varied. (author)

  18. Reductions of bacterial antibiotic resistance through five biological treatment processes treated municipal wastewater.

    Science.gov (United States)

    Yuan, Qing-Bin; Guo, Mei-Ting; Wei, Wu-Ji; Yang, Jian

    2016-10-01

    Wastewater treatment plants are hot spots for antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs). However, limited studies have been conducted to compare the reductions of ARB and ARGs by various biological treatment processes. The study explored the reductions of heterotrophic bacteria resistant to six groups of antibiotics (vancomycin, gentamicin, erythromycin, cephalexin, tetracycline, and sulfadiazine) and corresponding resistance genes (vanA, aacC1, ereA, ampC, tetA, and sulI) by five bench-scale biological reactors. Results demonstrated that membrane bioreactor (MBR) and sequencing batch reactor (SBR) significantly reduced ARB abundances in the ranges of 2.80∼3.54 log and 2.70∼3.13 log, respectively, followed by activated sludge (AS). Biological filter (BF) and anaerobic (upflow anaerobic sludge blanket, UASB) techniques led to relatively low reductions. In contrast, ARGs were not equally reduced as ARB. AS and SBR also showed significant potentials on ARGs reduction, whilst MBR and UASB could not reduce ARGs effectively. Redundancy analysis implied that the purification of wastewater quality parameters (COD, NH4 (+)-N, and turbidity) performed a positive correlation to ARB and ARGs reductions. PMID:27384166

  19. Molecular Biological basis for statin resistance in naturally statin-producing organisms

    DEFF Research Database (Denmark)

    Rems, Ana; Frandsen, Rasmus John Normand

    Secondary metabolites can be toxic to the organism producing them; therefore gene clusters for biosynthesis of secondary metabolites often include genes responsible for the organism’s self-resistance to the toxic compounds. One such gene cluster is the compactin (ML-236B) cluster in Penicillium...... secretion [1]. The mlcD gene encodes a putative ‘HMG-CoA reductase-like protein’, and mlcE encodes a putative efflux pump. However, the function of these two putative proteins has not yet been confirmed. We aim to elucidate the biological basis for compactin resistance in the compactin-producing organism. A...

  20. Bovine genetic resistance effects on biological traits of Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Biegelmeyer, P; Nizoli, L Q; da Silva, S S; dos Santos, T R B; Dionello, N J L; Gulias-Gomes, C C; Cardoso, F F

    2015-03-15

    This study aimed to verify the influence of bovine genetic resistance on biological traits of the Rhipicephalus (Boophilus) microplus tick. Genetic resistance or susceptibility was determined according to breeding values for tick counts, predicted using a dataset of 9007 Hereford and Braford (Hereford×Zebu) bovines naturally infested and raised under extensive production systems in southern Brazil. From a total of 974 Braford heifers born in 2008, 20 were classified as genetically tick-resistant and 20 classified as genetically tick-susceptible, and used to obtain the ticks samples used in this study. The 40 heifers were exposed to four subsequent artificial infestations with approximately 20,000 larvae at 14-day intervals. From the 19th to 23rd day of each infestation tick counts were performed on the left body side of the heifers. Engorged ticks were manually collected on the day of highest observed burden after each infestation. Tick counts on susceptible heifers were 5.5, 10.5, 11.1 and 6.9 times larger than on resistant heifers, respectively, after the first, second, third and fourth artificial infestations. In the third infestation, ticks from resistant heifers showed lower egg production index (Pticks from susceptible heifers. In the fourth infestation, ticks from susceptible group showed higher egg mass weight (Pticks from resistant heifers. Tick initial weights showed a positive association with egg production index in susceptible heifers (Presistant group (Pticks from resistant cattle. This shows that bovine genetic tick resistance, in addition to affecting the number of ticks carried by the animals, also affected the egg mass weight, egg production and nutrient indexes of ticks. The results of the present study imply that the selection of resistant animals could be used as a strategic tool for tick control in production systems, reducing infestation levels on cattle and environment. PMID:25648284

  1. Biological characteristics and resistance analysis of the novel fungicide SYP-1620 against Botrytis cinerea.

    Science.gov (United States)

    Zhang, Xiaoke; Wu, Dongxia; Duan, Yabing; Ge, Changyan; Wang, Jianxin; Zhou, Mingguo; Chen, Changjun

    2014-09-01

    SYP-1620, a quinone-outside-inhibitor (QoI), is a novel broad-spectrum fungicide. In this study, 108 isolates of Botrytis cinerea from different geographical regions in Jiangsu Province of China were characterized for baseline sensitivity to SYP-1620. The curves of baseline sensitivity were unimodal with a mean EC50 value of 0.0130±0.0109 μg/mL for mycelial growth, 0.01147±0.0062 μg/mL for spore germination, respectively. The biological characterization of SYP-1620 against B. cinerea was determined in vitro. The results indicated that SYP-1620 has a strong inhibiting effect on spore germination, mycelial growth, and respiration. The protective and curative test of SYP-1620 suggested that protective effect was better than curative either on strawberry leaves or on cucumber leaves in vivo. In addition, the biological characterization of SYP-1620-resistant mutants of B. cinerea was investigated. SYP-1620 has no cross-resistance with other types of fungicide. Compared to the sensitive isolates, the resistant mutants had lower mycelial growth and virulence but not differ in mycelial dry weight. Sequencing indicated that SYP-1620 resistance was associated with a single point mutation (G143A) in the cytochrome b gene.

  2. [Biological profile of tartrate-resistant acid phosphatase as a marker of bone resorption].

    Science.gov (United States)

    Rico, H; Iritia, M; Arribas, I; Revilla, M

    1990-12-01

    Tartrate-resistant serum acid phosphatase was measured in 123 subjects, 80 of which were normal and the rest pathologic, in order to define the profile and value of this parameter as a biological marker of osteoclastic activity. Normal subjects were divided into age groups based on the period where skeletal growth ends (under 20 years), at the age of menopause in women (50 years, between 20 and 50 years) and those over 50 years. There was an increase in tartrate-resistant serum acid phosphatase coinciding with puberty and no sex differences were observed after the 50 year mark, when women showed higher values than men (p less than 0.001). Such tartrate-resistant serum acid phosphatase increase, is reflected as higher values in the 50 year group than in the 20 to 50 year group (p less than 0.001), the only age limit where a negative significant correlation between tartrate-resistant serum acid phosphatase values and age could be observed (p less than 0.05). Values were higher up to the age of 20 years (p less than 0.001) than in any other older age group. Levels increased significantly (p less than 0.001 for both groups) in post-menopausal osteoporosis (n = 20) and in Paget's disease of bone (n = 15), and decreased significantly (p less than 0.05) in imperfect osteogenesis (n = 8), thus revealing its value as a biological marker of osteoclastic activity. PMID:2099535

  3. Corrosion resistance of titanium and some dental implant alloy in biological fluids

    International Nuclear Information System (INIS)

    The main purpose of this paper is the study of the long-term corrosion resistance of the titanium and dental alloy Ti-5Al-4V in physiological serum and artificial saliva of different pH values (acid and neutral) at 37 deg. C, reproducing the various biological environments that can be in contact with dental implants. The potentiostatic, potentiodynamic and linear polarisation measurements have been used to characterise the corrosion resistance of these materials during a period of about 1500 exposure hours. Also, the variation of open circuit potentials in time and with pH has been recorded for the same term. The potential gradients resulted from the pH changes were calculated; also, their variation in time were simulated for extreme, hypothetical conditions. The corrosion rates were determined. (authors)

  4. Biological and productive characteristics of apple cultivars resistant or tolerant to scab [Venturia inaequalis (Cooke) Wint.

    OpenAIRE

    Đorđević Boban S.; Vulić Todor B.; Đurović Dejan B.; Milatović Dragan P.; Zec Gordan N.; Radović Aleksandar R.

    2013-01-01

    Biological and productive characteristics of 11 scab-resistant apple cultivars were studied in the period 2011-2012 on the estate of the monastery Žiča in Central Serbia. Control cultivar for comparison was ‘Idared’, as the most spread apple cultivar in Serbia. The earliest blooming was found in cultivar ‘Topaz’, and the latest in cultivar ‘Rewena’. Based on the time of fruit maturation, three cultivars belong to the summer and autumn group, and five cultiv...

  5. Induced Resistance as a Mechanism of Biological Control by Lysobacter enzymogenes Strain C3.

    Science.gov (United States)

    Kilic-Ekici, Ozlem; Yuen, Gary Y

    2003-09-01

    ABSTRACT Induced resistance was found to be a mechanism for biological control of leaf spot, caused by Bipolaris sorokiniana, in tall fescue (Festuca arundinacea) using the bacterium Lysobacter enzymogenes strain C3. Resistance elicited by C3 suppressed germination of B. sorokiniana conidia on the phylloplane in addition to reducing the severity of leaf spot. The pathogen-inhibitory effect could be separated from antibiosis by using heat-inactivated cells of C3 that retained no antifungal activity. Application of live or heat-killed cells to tall fescue leaves resulted only in localized resistance confined to the treated leaf, whereas treatment of roots resulted in systemic resistance expressed in the foliage. The effects of foliar and root applications of C3 were long lasting, as evidenced by suppression of conidial germination and leaf spot development even when pathogen inoculation was delayed 15 days after bacterial treatment. When C3 population levels and germination of pathogen conidia was examined on leaf segments, germination percentage was reduced on all segments from C3-treated leaves compared with segments from non-treated leaves, but no dose-response relationship typical of antagonism was found. Induced resistance by C3 was not host or pathogen specific; foliar application of heat-killed C3 cells controlled B. sorokiniana on wheat and also was effective in reducing the severity of brown patch, caused by Rhizoctonia solani, on tall fescue. Treatments of tall fescue foliage or roots with C3 resulted in significantly elevated peroxidase activity compared with the control.

  6. Expression of a Magnaporthe grisea Elicitor and Its Biological Function in Activating Resistance in Rice

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The expression of a protein elicitor from Magnaporthe griesea and its biological function in activating resistance in rice (Oryza sativa L) were reported. The gene of elicitor was expressed in Escherichia coli cells and produced a His6-fusion protein with 42 kD apparent molecular weight on SDS-PAGE. The purified protein could induce the resistance to blast disease, with the control efficiency of 46.47% and 36.41% at the 14th day and the 21st day after blast inoculation, respectively.After treatment with the expressed protein, the phenylalanine ammonia-lyase (PAL) and peroxidase (POD) activities were promoted in rice plants, meanwhile, the transcription levels of STKM, FAD, PBZ1 and PR1 genes were increased in rice plants. Moreover, after comparing the profile of total rice leaf proteins on two-dimensional eiectrophoresis gel, about 14proteins were found to be increased in expression level after the expressed protein treatment. All the results indicated that the expressed protein could act as an elicitor to trigger the resistance in rice.

  7. Uncovering three-dimensional gradients in fibrillar orientation in an impact-resistant biological armour

    Science.gov (United States)

    Zhang, Y.; Paris, O.; Terrill, N. J.; Gupta, H. S.

    2016-05-01

    The complex hierarchical structure in biological and synthetic fibrous nanocomposites entails considerable difficulties in the interpretation of the crystallographic texture from diffraction data. Here, we present a novel reconstruction method to obtain the 3D distribution of fibres in such systems. An analytical expression is derived for the diffraction intensity from fibres, explaining the azimuthal intensity distribution in terms of the angles of the three dimensional fibre orientation distributions. The telson of stomatopod (mantis shrimp) serves as an example of natural biological armour whose high impact resistance property is believed to arise from the hierarchical organization of alpha chitin nanofibrils into fibres and twisted plywood (Bouligand) structures at the sub-micron and micron scale. Synchrotron microfocus scanning X-ray diffraction data on stomatopod telson were used as a test case to map the 3D fibre orientation across the entire tissue section. The method is applicable to a range of biological and biomimetic structures with graded 3D fibre texture at the sub-micron and micron length scales.

  8. Hybridization of an invasive shrub affects tolerance and resistance to defoliation by a biological control agent

    Science.gov (United States)

    Williams, Wyatt I.; Friedman, Jonathan M.; Gaskin, John F.; Norton, Andrew P.

    2014-01-01

    Evolution has contributed to the successful invasion of exotic plant species in their introduced ranges, but how evolution affects particular control strategies is still under evaluation. For instance, classical biological control, a common strategy involving the utilization of highly specific natural enemies to control exotic pests, may be negatively affected by host hybridization because of shifts in plant traits, such as root allocation or chemical constituents. We investigated introgression between two parent species of the invasive shrub tamarisk (Tamarix spp.) in the western United States, and how differences in plant traits affect interactions with a biological control agent. Introgression varied strongly with latitude of origin and was highly correlated with plant performance. Increased levels of T. ramosissima introgression resulted in both higher investment in roots and tolerance to defoliation and less resistance to insect attack. Because tamarisk hybridization occurs predictably on the western U.S. landscape, managers may be able to exploit this information to maximize control efforts. Genetic differentiation in plant traits in this system underpins the importance of plant hybridization and may explain why some biological control releases are more successful than others.

  9. Systems Biology Strategy Reveals PKC-delta is Key for Sensitizing TRAIL-Resistant Human Fibrosarcoma

    Directory of Open Access Journals (Sweden)

    Kentaro eHayashi

    2015-01-01

    Full Text Available Cancer cells are highly variable and resistant to therapeutic intervention. Recently, the use of the tumor necrosis factor related apoptosis-inducing ligand (TRAIL induced treatment is gaining momentum, due to TRAIL’s ability to specifically target cancers with limited effect on normal cells. However, several malignant cancer types still remain non-sensitive to TRAIL. Previously, we developed a dynamic computational model, based on perturbation-response approach, and predicted protein kinase C (PKC as the most effective target, with over 95% capacity to kill human fibrosarcoma (HT1080 in TRAIL stimulation (Piras, V. et al. 2011, Scientific Reports. Here, to validate the model prediction, which has significant implications for cancer treatment, we conducted experiments on two TRAIL-resistant cancer cell lines (HT1080 and HT29. Using PKC inhibitor Bisindolylmaleimide I, we first demonstrate, as predicted by our previous model, cell viability is significantly impaired with over 95% death of both cancer types. Next, to identify crucial PKC isoform from 10 known members, we analyzed their mRNA expressions in HT1080 cells and shortlisted 4 isoforms for siRNA knock-down (KD experiments. From these KDs, PKC-delta produced the most cancer cell death in conjunction with TRAIL. Overall, systems biology approach, combining model prediction with experimental validation, holds promise for TRAIL-based cancer therapy.

  10. Evolutionary malignant resistance of cells to damaging factors as common biological defence mechanism in neoplastic development. Review of conception.

    Science.gov (United States)

    Monceviciute-Eringiene, E

    2000-09-01

    Cells have some inborn resistance to harmful factors, which could be called physiological or natural resistance. The mechanisms of multixenobiotic resistance (MXR) and multidrug resistance (MDR) have common features in the formation of acquired resistance in microorganisms, carcinogenesis, tumour metastases and chemotherapy or irradiation. ATP-dependent membrane P-glycoprotein, as an MDR efflux pump, glutathione S-transferases and other products of evolutionary resistance-related genes arised for exportation and detoxification of cytotoxic xenobiotics and drugs are transmitted from bacteria to man. On the one hand, this evolutionary MXR as a common biological defence mechanism is a "driving" power to conserve homeostasis of cells, tissues and organs. On the other hand, mutation, selection and simplification of properties are the causes of functional and morphological changes in tumour cells which regress to a more primitive mode of existence (atavism) for adaptation to survival. In the present work are presented data on the forms of E. coli resistant to antibiotics and of sarcoma 45 resistant to alkylic preparations. They may be helpful in revealing the causes of resistance and acquired accelerated growth of cells. The development of tumours as fibromas 14-15 years following injection of a vital dye trypan blue into human skin supports our conception that neoplastic growth is a particular case of the evolutionary resistance of cells adapted to the damaging factors. So, tumour cells adopting the enhancement mechanisms of general biological persistent resistance, i. e. undergoing repeated cycles of malignancy enhancement, adapt themselves to survive under the changed unfavourable conditions. PMID:11144527

  11. Construction of biological control strain of Trichoderma viride and study of their ability to induce plant disease resistance

    Institute of Scientific and Technical Information of China (English)

    LIU Shi-wang; GUO Ze-jian

    2004-01-01

    @@ Plant diseases heavily affct plant growth and crop yield even in modern agriculture. Control its difficult because pathogens mutate frequently, and this leads in frequent breaking of disease resistance in commercial cultivars. The excessive application of chemical pesticides is not only producing pesticideresistant pathogens, but it is harming the environment threatening the health of human beings.Therefore, the use of biological control agents (BCA) may provide an environmental friendly alternative to chemicals for plant disease control. Hypersensitive response (HR) and systemic acquired resistance (SAR) are the typical expressions of plant defense reactions. Once SAR is established,, the plants exhibits a broad-spectrum of disease resistance against pathogen attack. Researchers have identified elicitor proteins, such as elicitins and harpins, which activate plant defense reactions. It would be useful to explore the possibility of using biological control agents to induce a status of SAR in crop plants.

  12. Combined efficacy of biologically synthesized silver nanoparticles and different antibiotics against multidrug-resistant bacteria

    Directory of Open Access Journals (Sweden)

    Naqvi SZ

    2013-08-01

    Full Text Available Syed Zeeshan Haider Naqvi, Urooj Kiran, Muhammad Ishtiaq Ali, Asif Jamal, Abdul Hameed, Safia Ahmed, Naeem Ali Microbiology Research Laboratory, Department of Microbiology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan Abstract: Biological synthesis of nanoparticles is a growing innovative approach that is relatively cheaper and more environmentally friendly than current physicochemical processes. Among various microorganisms, fungi have been found to be comparatively more efficient in the synthesis of nanomaterials. In this research work, extracellular mycosynthesis of silver nanoparticles (AgNPs was probed by reacting the precursor salt of silver nitrate (AgNO3 with culture filtrate of Aspergillus flavus. Initially, the mycosynthesis was regularly monitored by ultraviolet-visible spectroscopy, which showed AgNP peaks of around 400–470 nm. X-ray diffraction spectra revealed peaks of different intensities with respect to angle of diffractions (2θ corresponding to varying configurations of AgNPs. Transmission electron micrographs further confirmed the formation of AgNPs in size ranging from 5–30 nm. Combined and individual antibacterial activities of the five conventional antibiotics and AgNPs were investigated against eight different multidrug-resistant bacterial species using the Kirby–Bauer disk-diffusion method. The decreasing order of antibacterial activity (zone of inhibition in mm of antibiotics, AgNPs, and their conjugates against bacterial group (average was; ciprofloxacin + AgNPs (23 > imipenem + AgNPs (21 > gentamycin + AgNPs (19 > vancomycin + AgNPs (16 > AgNPs (15 > imipenem (14 > trimethoprim + AgNPs (14 > ciprofloxacin (13 > gentamycin (11 > vancomycin (4 > trimethoprim (0. Overall, the synergistic effect of antibiotics and nanoparticles resulted in a 0.2–7.0 (average, 2.8 fold-area increase in antibacterial activity, which clearly revealed that nanoparticles can be effectively used in

  13. Cellular resistance in radio- and chemotherapy: biological basis and strategies for circumvention

    International Nuclear Information System (INIS)

    In this review the author points out that resistance to cytotoxic drugs is a complex, multifactorial phenomenon involving a range of mechanisms. There is accumulating evidence that these are of relevance to both inherent and acquired resistance in the clinic. Demonstration that mechanisms of drug and radiation resistance are closely linked provides a basis for the related patterns of responsiveness observed in clinical practice. Strategies for circumvention of resistance mechanisms will depend for success upon finding ways of improving therapeutic ratio. Optimal clinical trial of resistance circumvention strategies will require the use of quantitative markers of resistance mechanisms in tumour and normal tissues. (author)

  14. Impact of the ahas transgene for herbicides resistance on biological nitrogen fixation and yield of soybean.

    Science.gov (United States)

    Hungria, Mariangela; Nakatani, André Shigueyoshi; Souza, Rosinei Aparecida; Sei, Fernando Bonafé; de Oliveira Chueire, Ligia Maria; Arias, Carlos Arrabal

    2015-02-01

    Studies on the effects of transgenes in soybean [Glycine max (L.) Merr.] and the associated use of specific herbicides on biological nitrogen fixation (BNF) are still few, although it is important to ensure minimal impacts on benefits provided by the root-nodule symbiosis. Cultivance CV127 transgenic soybean is a cultivar containing the ahas gene, which confers resistance to herbicides of the imidazolinone group. The aim of this study was to assess the effects of the ahas transgene and of imidazolinone herbicide on BNF parameters and soybean yield. A large-scale set of field experiments was conducted, for three cropping seasons, at nine sites in Brazil, with a total of 20 trials. The experiment was designed as a completely randomized block with four replicates and the following treatments: (T1) near isogenic transgenic soybean (Cultivance CV127) + herbicide of the imidazolinone group (imazapyr); (T2) near isogenic transgenic soybean + conventional herbicides; and (T3) parental conventional soybean (Conquista) + conventional herbicides; in addition, two commercial cultivars were included, Monsoy 8001 (M-SOY 8001) (T4), and Coodetec 217 (CD 217) (T5). At the R2 growth stage, plants were collected and BNF parameters evaluated. In general, there were no effects on BNF parameters due to the transgenic trait or associated with the specific herbicide. Similarly, at the final harvest, no grain-yield effects were detected related to the ahas gene or to the specific herbicide. However, clear effects on BNF and grain yield were attributed to location and cropping season.

  15. Assessing the emergence of resistance: the absence of biological cost in vivo may compromise fosfomycin treatments for P. aeruginosa infections.

    Directory of Open Access Journals (Sweden)

    Alexandro Rodríguez-Rojas

    Full Text Available BACKGROUND: Fosfomycin is a cell wall inhibitor used efficiently to treat uncomplicated urinary tract and gastrointestinal infections. A very convenient feature of fosfomycin, among others, is that although the expected frequency of resistant mutants is high, the biological cost associated with mutation impedes an effective growth rate, and bacteria cannot offset the obstacles posed by host defenses or compete with sensitive bacteria. Due to the current scarcity of new antibiotics, fosfomycin has been proposed as an alternative treatment for other infections caused by a wide variety of bacteria, particularly Pseudomonas aeruginosa. However, whether fosfomycin resistance in P. aeruginosa provides a fitness cost still remains unknown. PRINCIPAL FINDINGS: We herein present experimental evidence to show that fosfomycin resistance cannot only emerge easily during treatment, but that it is also cost-free for P. aeruginosa. We also tested if, as has been reported for other species such as Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis, fosfomycin resistant strains are somewhat compromised in their virulence. As concerns colonization, persistence, lung damage, and lethality, we found no differences between the fosfomycin resistant mutant and its sensitive parental strain. The probability of acquisition in vitro of resistance to the combination of fosfomycin with other antibiotics (tobramycin and imipenem has also been studied. While the combination of fosfomycin with tobramycin makes improbable the emergence of resistance to both antibiotics when administered together, the combination of fosfomycin plus imipenem does not avoid the appearance of mutants resistant to both antibiotics. CONCLUSIONS: We have reached the conclusion that the use of fosfomycin for P. aeruginosa infections, even in combined therapy, might not be as promising as expected. This study should encourage the scientific community to assess the in vivo cost of resistance

  16. Systems biology reveals new strategies for personalizing cancer medicine and confirms the role of PTEN in resistance to trastuzumab.

    Science.gov (United States)

    Faratian, Dana; Goltsov, Alexey; Lebedeva, Galina; Sorokin, Anatoly; Moodie, Stuart; Mullen, Peter; Kay, Charlene; Um, In Hwa; Langdon, Simon; Goryanin, Igor; Harrison, David J

    2009-08-15

    Resistance to targeted cancer therapies such as trastuzumab is a frequent clinical problem not solely because of insufficient expression of HER2 receptor but also because of the overriding activation states of cell signaling pathways. Systems biology approaches lend themselves to rapid in silico testing of factors, which may confer resistance to targeted therapies. Inthis study, we aimed to develop a new kinetic model that could be interrogated to predict resistance to receptor tyrosine kinase (RTK) inhibitor therapies and directly test predictions in vitro and in clinical samples. The new mathematical model included RTK inhibitor antibody binding, HER2/HER3 dimerization and inhibition, AKT/mitogen-activated protein kinase cross-talk, and the regulatory properties of PTEN. The model was parameterized using quantitative phosphoprotein expression data from cancer cell lines using reverse-phase protein microarrays. Quantitative PTEN protein expression was found to be the key determinant of resistance to anti-HER2 therapy in silico, which was predictive of unseen experiments in vitro using the PTEN inhibitor bp(V). When measured in cancer cell lines, PTEN expression predicts sensitivity to anti-HER2 therapy; furthermore, this quantitative measurement is more predictive of response (relative risk, 3.0; 95% confidence interval, 1.6-5.5; P biology approach has successfully been used to stratify patients for personalized therapy in cancer and is further compelling evidence that PTEN, appropriately measured in the clinical setting, refines clinical decision making in patients treated with anti-HER2 therapies.

  17. 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.

  18. Limiting the Spread of Resistant Pneumococci: Biological and Epidemiologic Evidence for the Effectiveness of Alternative Interventions

    OpenAIRE

    Schrag, Stephanie J.; Beall, Bernard; Scott F Dowell

    2000-01-01

    Streptococcus pneumoniae infections are a leading cause of respiratory illness in young children, the elderly, and persons with chronic medical conditions. The emergence of multidrug-resistant pneumococci has compromised the effectiveness of antibiotic therapy for pneumococcal infections. As antibiotic-resistant strains increase in prevalence, there is a need for interventions that minimize the spread of resistant pneumococci. In this review we provide a framework for understanding the spread...

  19. On the multiscale origins of fracture resistance in human bone and its biological degradation

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, Elizabeth A.; Barth, Holly D.; Ritchie, Robert O.

    2012-03-09

    Akin to other mineralized tissues, human cortical bone can resist deformation and fracture due to the nature of its hierarchical structure, which spans the molecular to macroscopic length-scales. Deformation at the smallest scales, mainly through the composite action of the mineral and collagen, contributes to bone?s strength or intrinsic fracture resistance, while crack-tip shielding mechanisms active on the microstructural scale contribute to the extrinsic fracture resistance once cracking begins. The efficiency with which these structural features can resist fracture at both small and large length-scales becomes severely degraded with such factors as aging, irradiation and disease. Indeed aging and irradiation can cause changes to the cross-link profile at fibrillar length-scales as well as changes at the three orders of magnitude larger scale of the osteonal structures, both of which combine to inhibit the bone's overall resistance to the initiation and growth of cracks.

  20. An update on molecular biology and drug resistance mechanisms of multiple myeloma.

    Science.gov (United States)

    Mutlu, Pelin; Kiraz, Yağmur; Gündüz, Ufuk; Baran, Yusuf

    2015-12-01

    Multiple myeloma (MM), a neoplasm of plasma cells, is the second most common hematological malignancy. Incidance rates increase after age 40. MM is most commonly seen in men and African-American population. There are several factors to this, such as obesity, environmental factors, family history, genetic factors and monoclonal gammopathies of undetermined significance (MGUS) that have been implicated as potentially etiologic. Development of MM involves a series of complex molecular events, including chromosomal abnormalities, oncogene activation and growth factor dysregulation. Chemotherapy is the most commonly used treatment strategy in MM. However, MM is a difficult disease to treat because of its marked resistance to chemotherapy. MM has been shown to be commonly multidrug resistance (MDR)-negative at diagnosis and associated with a high incidence of MDR expression at relapse. This review deals with the molecular aspects of MM, drug resistance mechanisms during treatment and also possible new applications for overcoming drug resistance. PMID:26235594

  1. Fast and Accurate Microplate Method (Biolog MT2) for Detection of Fusarium Fungicides Resistance/Sensitivity

    OpenAIRE

    Frąc, Magdalena; Gryta, Agata; Oszust, Karolina; Kotowicz, Natalia

    2016-01-01

    The need for finding fungicides against Fusarium is a key step in the chemical plant protection and using appropriate chemical agents. Existing, conventional methods of evaluation of Fusarium isolates resistance to fungicides are costly, time-consuming and potentially environmentally harmful due to usage of high amounts of potentially toxic chemicals. Therefore, the development of fast, accurate and effective detection methods for Fusarium resistance to fungicides is urgently required. MT2 mi...

  2. Adiposity, Biological Markers of Disease, and Insulin Resistance in Mexican American Adolescents, 2004-2005

    Directory of Open Access Journals (Sweden)

    Anne R. Rentfro, PhD, RN

    2011-03-01

    Full Text Available IntroductionRates of obesity and overweight, which frequently lead to type 2 diabetes, have increased dramatically among US children during the past 30 years. We analyzed associations between insulin resistance and other markers of disease in a sample of Mexican American adolescents from a severely disadvantaged community on the Texas-Mexico border.MethodsWe analyzed results from 325 students from 1 high school in this descriptive study. We measured height, weight, waist circumference, blood pressure, blood glucose, and lipids; calculated body mass index; and estimated insulin resistance.ResultsApproximately 50% of our sample (mean age, 16 y were overweight or obese, and more participants were obese than overweight. More than 40% had high waist circumference, and 66% had elevated high-density lipoprotein cholesterol. These characteristics were already present in the youngest participants (aged 12 y. Although only 1% of participants had elevated fasting blood glucose, 27% exhibited insulin resistance and most of these were also obese. Similarly, participants with high waist circumference were more likely to exhibit insulin resistance than those with normal waist circumference.ConclusionParticipants in this sample had insulin resistance, a potent predictor of diabetes. Two markers, low high-density lipoprotein cholesterol and high waist circumference, were strongly linked to insulin resistance; the surrogate for central adiposity, waist circumference, exhibited strong association. We identified high levels of obesity and markers for future disease in our sample. These findings emphasize the need to address insulin resistance at least as early as adolescence to prevent adverse economic, social, and health consequences.

  3. Molecular and cellular biology of resistance to Phytophthora infestans in Solanum species

    NARCIS (Netherlands)

    Vleeshouwers, V.G.A.A.

    2001-01-01

    Ever since the late blight epidemics of the mid-nineteenth century, man has endeavored to protect his potato crop. Every year, extensive chemical protection is applied, which is expensive and may be harmful to the natural environment. The use of resistant potato cultivars would provide an elegant al

  4. Proteomics of Skeletal Muscle: Focus on Insulin Resistance and Exercise Biology

    Directory of Open Access Journals (Sweden)

    Atul S. Deshmukh

    2016-02-01

    Full Text Available Skeletal muscle is the largest tissue in the human body and plays an important role in locomotion and whole body metabolism. It accounts for ~80% of insulin stimulated glucose disposal. Skeletal muscle insulin resistance, a primary feature of Type 2 diabetes, is caused by a decreased ability of muscle to respond to circulating insulin. Physical exercise improves insulin sensitivity and whole body metabolism and remains one of the most promising interventions for the prevention of Type 2 diabetes. Insulin resistance and exercise adaptations in skeletal muscle might be a cause, or consequence, of altered protein expressions profiles and/or their posttranslational modifications (PTMs. Mass spectrometry (MS-based proteomics offer enormous promise for investigating the molecular mechanisms underlying skeletal muscle insulin resistance and exercise-induced adaptation; however, skeletal muscle proteomics are challenging. This review describes the technical limitations of skeletal muscle proteomics as well as emerging developments in proteomics workflow with respect to samples preparation, liquid chromatography (LC, MS and computational analysis. These technologies have not yet been fully exploited in the field of skeletal muscle proteomics. Future studies that involve state-of-the-art proteomics technology will broaden our understanding of exercise-induced adaptations as well as molecular pathogenesis of insulin resistance. This could lead to the identification of new therapeutic targets.

  5. Effects of Tebufenozide on the Biological Characteristics of Beet Armyworm (Spodoptera exigua Hübner) and Its Resistance Selection

    Institute of Scientific and Technical Information of China (English)

    LIU Wei-wei; MU Wei; ZHU Bing-yu; LIU Feng

    2008-01-01

    In this article, the selection of tebufenozide to beet armyworm (Spodoptera exigua Hubner) was studied by the treatments to alternative generations' 3rd-instar larvae with LC50 dose and to continuous generations' larvae with LC10 dose; the effects of tebufenozide on the biological characteristics of current and subsequent generations were examined by the treatments to 3rd-instar larvae and egg pods in different concentrations. After treatments with LC50 dose till F11, the toxicity of tebufenozide to beet armyworm had no significant change, whereas the pupation rate, pupal weight, and fecundity were reduced markedly. After treatments with LC10 dose till F19, the beet armyworm only developed 3.52-fold resistance, and the main biological characteristics were nearly accordant in each generation. The livability was reduced 72 h later after treatments to 3rd-instar larvae, respectively in 2.5-40 (ig mL-', and larval duration, pupation rate, and pupal weight changed considerably with the increase in concentrations. The fecundity, larval livability, larval weight and pupal weight of subsequent generations were reduced as the dose increased over 10 ug mL-1. The hatching rate of egg pods did not differ with that of the controls obviously after treatment in 10-300 ug mL-1. But the larval livability, larval weight and pupal weight were reduced when eggs were exposed to 50 ug mL-1 dose or more. The results indicated that tebufenozide had low resistance risk to the current and subsequent generations of beet armyworm even if tebufenozide had significant effects on the biological characteristics of this insect.

  6. Adiposity, Biological Markers of Disease, and Insulin Resistance in Mexican American Adolescents, 2004-2005

    OpenAIRE

    Anne R. Rentfro, PhD, RN; Jeanette C. Nino, MS; Rosa M. Pones, MPH, RN; Wendy Innis-Whitehouse, PhD; Cristina S. Barroso, DrPH; Mohammed H. Rahbar, PhD; Joseph B. McCormick, MD, MS; Susan P. Fisher-Hoch, MD, MBBS, MSc, MRCPath

    2011-01-01

    Introduction Rates of obesity and overweight, which frequently lead to type 2 diabetes, have increased dramatically among US children during the past 30 years. We analyzed associations between insulin resistance and other markers of disease in a sample of Mexican American adolescents from a severely disadvantaged community on the Texas-Mexico border. Methods We analyzed results from 325 students from 1 high school in this descriptive study. We measured height, weight, waist circumference, blo...

  7. Proteomics of Skeletal Muscle: Focus on Insulin Resistance and Exercise Biology

    OpenAIRE

    Deshmukh, Atul S.

    2016-01-01

    Skeletal muscle is the largest tissue in the human body and plays an important role in locomotion and whole body metabolism. It accounts for ~80% of insulin stimulated glucose disposal. Skeletal muscle insulin resistance, a primary feature of Type 2 diabetes, is caused by a decreased ability of muscle to respond to circulating insulin. Physical exercise improves insulin sensitivity and whole body metabolism and remains one of the most promising interventions for the prevention of Type 2 diabe...

  8. Environmental and biological factors influencing the UV-C resistance of Listeria monocytogenes.

    Science.gov (United States)

    Gayán, E; Serrano, M J; Pagán, R; Álvarez, I; Condón, S

    2015-04-01

    In this investigation, the effect of microbiological factors (strain, growth phase, exposition to sublethal stresses, and photorepair ability), treatment medium characteristics (pH, water activity, and absorption coefficient), and processing parameters (dose and temperature) on the UV resistance of Listeria monocytogenes was studied. The dose to inactivate 99.99% of the initial population of the five strains tested ranged from 21.84 J/mL (STCC 5672) to 14.66 J/mL (STCC 4031). The UV inactivation of the most resistant strain did not change in different growth phases and after exposure to sublethal heat, acid, basic, and oxidative shocks. The pH and water activity of the treatment medium did not affect the UV resistance of L. monocytogenes, whereas the inactivation rate decreased exponentially with the absorption coefficient. The lethal effect of UV radiation increased synergistically with temperature between 50 and 60 °C (UV-H treatment). A UV-H treatment of 27.10 J/mL at 55 °C reached 2.99 and 3.69 Log10 inactivation cycles of L. monocytogenes in orange juice and vegetable broth, and more than 5 Log10 cycles in apple juice and chicken broth. This synergistic effect opens the possibility to design UV combined processes for the pasteurization of liquid foods with high absorptivity.

  9. Biological synthesis of fluorescent nanoparticles by cadmium and tellurite resistant Antarctic bacteria: exploring novel natural nanofactories

    OpenAIRE

    Plaza, D. O.; Gallardo, C.; Straub, Y. D.; Bravo, D.; Pérez-Donoso, J. M.

    2016-01-01

    Background Fluorescent nanoparticles or quantum dots (QDs) have been intensely studied for basic and applied research due to their unique size-dependent properties. There is an increasing interest in developing ecofriendly methods to synthesize these nanoparticles since they improve biocompatibility and avoid the generation of toxic byproducts. The use of biological systems, particularly prokaryotes, has emerged as a promising alternative. Recent studies indicate that QDs biosynthesis is rela...

  10. Synergistic and additive effect of oregano essential oil and biological silver nanoparticles against multidrug-resistant bacterial strains

    Directory of Open Access Journals (Sweden)

    Sara eScandorieiro

    2016-05-01

    Full Text Available Bacterial resistance to conventional antibiotics has become a clinical and public health problem, making therapeutic decisions more challenging. Plant compounds and nanodrugs have been proposed as potential antimicrobial alternatives. Studies have shown that oregano (Origanum vulgare essential oil (OEO and silver nanoparticles have potent antibacterial activity, also against multidrug-resistant strains; however, the strong organoleptic characteristics of OEO and the development of resistance to these metal nanoparticles can limit their use. This study evaluated the antibacterial effect of a two-drug combination of biologically synthesized silver nanoparticles (bio-AgNP, produced by Fusarium oxysporum, and OEO against Gram-positive and Gram-negative bacteria, including multidrug-resistant strains. OEO and bio-AgNP showed bactericidal effects against all seventeen strains tested, with minimal inhibitory concentrations (MIC ranging from 0.298 to 1.193 mg/mL and 62.5 to 250 µM, respectively. Time-kill curves indicated that OEO acted rapidly (within 10 min, while the metallic nanoparticles took 4 h to kill Gram-negative bacteria and 24 h to kill Gram-positive bacteria. The combination of the two compounds resulted in a synergistic or additive effect, reducing their MIC values and reducing the time of action compared to bio-AgNP used alone, i.e., 20 min for Gram-negative bacteria and 7 h for Gram-positive bacteria. Scanning electron microscopy (SEM revealed similar morphological alterations in Staphylococcus aureus (non-methicillin-resistant S. aureus, non-MRSA cells exposed to three different treatments (OEO, bio-AgNP and combination of the two, which appeared cell surface blebbing. Individual and combined treatments showed reduction in cell density and decrease in exopolysaccharide matrix compared to untreated bacterial cells. It indicated that this composition have an antimicrobial activity against S. aureus by disrupting cells. Both compounds

  11. Synergistic and Additive Effect of Oregano Essential Oil and Biological Silver Nanoparticles against Multidrug-Resistant Bacterial Strains.

    Science.gov (United States)

    Scandorieiro, Sara; de Camargo, Larissa C; Lancheros, Cesar A C; Yamada-Ogatta, Sueli F; Nakamura, Celso V; de Oliveira, Admilton G; Andrade, Célia G T J; Duran, Nelson; Nakazato, Gerson; Kobayashi, Renata K T

    2016-01-01

    Bacterial resistance to conventional antibiotics has become a clinical and public health problem, making therapeutic decisions more challenging. Plant compounds and nanodrugs have been proposed as potential antimicrobial alternatives. Studies have shown that oregano (Origanum vulgare) essential oil (OEO) and silver nanoparticles have potent antibacterial activity, also against multidrug-resistant strains; however, the strong organoleptic characteristics of OEO and the development of resistance to these metal nanoparticles can limit their use. This study evaluated the antibacterial effect of a two-drug combination of biologically synthesized silver nanoparticles (bio-AgNP), produced by Fusarium oxysporum, and OEO against Gram-positive and Gram-negative bacteria, including multidrug-resistant strains. OEO and bio-AgNP showed bactericidal effects against all 17 strains tested, with minimal inhibitory concentrations (MIC) ranging from 0.298 to 1.193 mg/mL and 62.5 to 250 μM, respectively. Time-kill curves indicated that OEO acted rapidly (within 10 min), while the metallic nanoparticles took 4 h to kill Gram-negative bacteria and 24 h to kill Gram-positive bacteria. The combination of the two compounds resulted in a synergistic or additive effect, reducing their MIC values and reducing the time of action compared to bio-AgNP used alone, i.e., 20 min for Gram-negative bacteria and 7 h for Gram-positive bacteria. Scanning electron microscopy (SEM) revealed similar morphological alterations in Staphylococcus aureus (non-methicillin-resistant S. aureus, non-MRSA) cells exposed to three different treatments (OEO, bio-AgNP and combination of the two), which appeared cell surface blebbing. Individual and combined treatments showed reduction in cell density and decrease in exopolysaccharide matrix compared to untreated bacterial cells. It indicated that this composition have an antimicrobial activity against S. aureus by disrupting cells. Both compounds showed very low

  12. Synergistic and Additive Effect of Oregano Essential Oil and Biological Silver Nanoparticles against Multidrug-Resistant Bacterial Strains

    Science.gov (United States)

    Scandorieiro, Sara; de Camargo, Larissa C.; Lancheros, Cesar A. C.; Yamada-Ogatta, Sueli F.; Nakamura, Celso V.; de Oliveira, Admilton G.; Andrade, Célia G. T. J.; Duran, Nelson; Nakazato, Gerson; Kobayashi, Renata K. T.

    2016-01-01

    Bacterial resistance to conventional antibiotics has become a clinical and public health problem, making therapeutic decisions more challenging. Plant compounds and nanodrugs have been proposed as potential antimicrobial alternatives. Studies have shown that oregano (Origanum vulgare) essential oil (OEO) and silver nanoparticles have potent antibacterial activity, also against multidrug-resistant strains; however, the strong organoleptic characteristics of OEO and the development of resistance to these metal nanoparticles can limit their use. This study evaluated the antibacterial effect of a two-drug combination of biologically synthesized silver nanoparticles (bio-AgNP), produced by Fusarium oxysporum, and OEO against Gram-positive and Gram-negative bacteria, including multidrug-resistant strains. OEO and bio-AgNP showed bactericidal effects against all 17 strains tested, with minimal inhibitory concentrations (MIC) ranging from 0.298 to 1.193 mg/mL and 62.5 to 250 μM, respectively. Time-kill curves indicated that OEO acted rapidly (within 10 min), while the metallic nanoparticles took 4 h to kill Gram-negative bacteria and 24 h to kill Gram-positive bacteria. The combination of the two compounds resulted in a synergistic or additive effect, reducing their MIC values and reducing the time of action compared to bio-AgNP used alone, i.e., 20 min for Gram-negative bacteria and 7 h for Gram-positive bacteria. Scanning electron microscopy (SEM) revealed similar morphological alterations in Staphylococcus aureus (non-methicillin-resistant S. aureus, non-MRSA) cells exposed to three different treatments (OEO, bio-AgNP and combination of the two), which appeared cell surface blebbing. Individual and combined treatments showed reduction in cell density and decrease in exopolysaccharide matrix compared to untreated bacterial cells. It indicated that this composition have an antimicrobial activity against S. aureus by disrupting cells. Both compounds showed very low

  13. Codling Moth, Cydia pomonella (Lepidoptera: Tortricidae – Major Pest in Apple Production: an Overview of its Biology, Resistance, Genetic Structure and Control Strategies

    Directory of Open Access Journals (Sweden)

    Ivana Pajač

    2011-06-01

    Full Text Available The codling moth Cydia pomonella (CM (Linnaeus is a key pest in pome fruit production with a preference for apple. The pest is very adaptable to different climatic conditions and is known for developing resistance to several chemical groups of insecticides. Because of these reasons, the populations of codling moth are differentiated in many ecotypes of various biological and physiological development requirements. The article provides a bibliographic review of investigation about: morphology, biology, dispersal, damages, resistance to insecticides, population genetic structure and genetic control of this pest.

  14. Resistance and susceptibility of alfalfa (Medicago sativa L.) cultivars to the aphid Therioaphis maculata (Homoptera:Aphididae): insect biology and cultivar evaluation

    Institute of Scientific and Technical Information of China (English)

    ALEXANDRE DE ALMEIDA E SILVA; ELENICE MOURO VARANDA; JOS(E) RICARDO BAROSELA

    2006-01-01

    Biology of the aphid Therioaphis maculata was studied on alfalfa (Medicago sativa L.), including four resistant (Mesa-Sirsa, CUF101, Baker and Lahontan) and two susceptible (ARC and Caliverde) alfalfa cultivars, and one of the most cropped Brazilian cultivars, Crioula. Under controlled conditions, antibiosis (i.e., reduced longevity, fecundity and increased mortality of the aphid) was observed mainly on the resistant alfalfa cultivars,except on Lahontan. Crioula seemed to be tolerant to aphids. Present data support geographic limitation usage of cultivars, and we suggest Baker and Mesa-Sirsa as sources of antibiosis,and provide biological information of a tropical T. maculata biotype on alfalfa.

  15. Biological and physical approaches to improve induced resistance against green mold of stored citrus fruit.

    Science.gov (United States)

    Arras, G; Dhallewin, G; Petretto, A; Marceddu, S; Loche, M; Agabbio, M

    2005-01-01

    Health and environmental concerns have point out the need to improve or change several manufacturing steps in the food chain. In this context particular attention should be given to the technologies involved in fruits and vegetables production. Nearly all fresh fruit and vegetables are subjected to different periods of storage and/or shelf-life before of their consumption. This implies the need to protect the commodities from microbial spoilage. Some Citrus species (e.g. lemon and grapefruit) may be stored for several months before consumption and then post-harvest treatments are essential to contain green (Penicillium digitatum) and blue (P. italicum) moulds. Alternative approaches to chemicals usually have a lower efficacy in containing rots but fulfill the consumer's expectation. Among the alternative strategies, the improvement of host natural resistance is promising. In this regard, we report some results concerning the use of biotic (yeast) and abiotic agents as inducers of phytoalexin (i.e. scoparone and/or scopoletin) accumulation in Citrus rind and its importance in the control of fungal decay. In all experiments the inducers were applied on fruits before or 24 h after inoculation with P. digitatum and the rot severity was monitored 7 days later. The accumulation of phytoalexins was monitored according to a standard methodology by HPLC. In all experiments a positive correlation was found between increase of the phytoalexin scoparone in host tissue and reduction of decay.

  16. Expression of multidrug resistance proteins P-glycoprotein, multidrug resistance protein 1, breast cancer resistance protein and lung resistance related protein in locally advanced bladder cancer treated with neoadjuvant chemotherapy: biological and clinical implications.

    NARCIS (Netherlands)

    Diestra, JE; Condom, E; Muro, XG Del; Scheffer, G.L.; Perez, J; Zurita, AJ; Munoz-Segui, J; Vigues, F; Scheper, R.J.; Capella, G; Germa-Lluch, JR; Izquierdo, M.A.

    2003-01-01

    PURPOSE: Resistance to chemotherapy is a major obstacle to overcome in the conservative treatment of patients with locally advanced bladder cancer (LABC). We investigated the predictive value of the response to neoadjuvant chemotherapy (NACT) and prognosis of the expression of multidrug resistance (

  17. Compatibility of host plant resistance and biological control of the two-spotted spider mite Tetranychus urticae in the ornamental crop Gerbera

    NARCIS (Netherlands)

    Krips, O.E.; Willems, P.E.L.; Dicke, M.

    1999-01-01

    We investigated the compatibility of host plant resistance to the spider mite Tetranychus urticae Koch in the ornamental crop gerbera with the use of the predatory mite Phytoseiulus persimilis Athias-Henriot for biological control. We used four gerbera cultivars on which the intrinsic rate of popula

  18. Do Offspring of Insects Feeding on Defoliation-Resistant Trees Have Better Biological Performance When Exposed to Nutritionally-Imbalanced Food?

    Science.gov (United States)

    Quezada-Garcia, Roberto; Fuentealba, Alvaro; Nguyen, Ngoc; Bauce, Éric

    2015-01-01

    White spruce (Picea glauca (Moench) Voss) trees that are resistant or susceptible to spruce budworm (Choristoneura fumiferana (Clem.)) attack were identified in a southern Quebec plantation. Due to high mortality-induced selective pressures imposed by resistant trees on spruce budworm larvae, insects that survive on resistant trees exhibited greater biological performance than those on susceptible trees. We tested the hypothesis that this better biological performance is maintained across generations when progeny were subjected to nutritional stress. We collected pupae from resistant and susceptible trees (phenotype). Adults were reared under controlled laboratory conditions. Progeny were subsequently reared on two types of artificial diet (high vs. low quality). Low quality diet simulated food quality deterioration during outbreak conditions. Results confirmed that surviving insects collected from resistant trees have better performance than those from susceptible trees. Offspring performance (pupal mass, developmental time) was affected only by diet quality. These results suggest that adaptive advantages that would be acquired from parents fed on resistant trees are lost when progeny are exposed to nutritionally-imbalanced food, but the effects persist when larvae are fed a balanced diet. Offspring mortality, fecundity and fertility were positively influenced by parental origin (tree phenotype).

  19. Study of the surface wear resistance and biological properties of the Ti-Zr-Nb-Sn alloy for dental restoration.

    Science.gov (United States)

    Hu, Xin; Wei, Qiang; Li, Chang-Yi; Deng, Jia-Yin; Liu, Shuang; Zhang, Lian-Yun

    2010-10-01

    A new titanium alloy (Ti-12.5Zr-3Nb-2.5Sn) was developed to meet the needs of clinical requirements for medical titanium alloys and improve the properties of existing titanium alloys. The as-prepared alloy was solution treated at 500 °C for 3 h in vacuum followed by water quenching. Tensile, wear and hardness tests were carried out to examine the mechanical properties of the Ti-Zr-Nb-Sn alloy. Oral mucous membrane irritation test was performed to evaluate the surface biological properties of the Ti-Zr-Nb-Sn alloy. The results suggested that the surface hardness and wear-resistant properties of the Ti-12.5Zr-3Nb-2.5Sn alloy were superior to commercially pure Ti. The oral mucous irritation test showed that all samples had no mucous membrane irritation. It indicates that Ti-12.5Zr-3Nb-2.5Sn has large potential to be used as dental restoration material.

  20. Study of the surface wear resistance and biological properties of the Ti-Zr-Nb-Sn alloy for dental restoration

    Energy Technology Data Exchange (ETDEWEB)

    Hu Xin; Li Changyi; Deng Jiayin; Liu Shuang; Zhang Lianyun [School of Dentistry, Tianjin Medical University, Tianjin 300070 (China); Wei Qiang [Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China)

    2010-10-01

    A new titanium alloy (Ti-12.5Zr-3Nb-2.5Sn) was developed to meet the needs of clinical requirements for medical titanium alloys and improve the properties of existing titanium alloys. The as-prepared alloy was solution treated at 500 {sup 0}C for 3 h in vacuum followed by water quenching. Tensile, wear and hardness tests were carried out to examine the mechanical properties of the Ti-Zr-Nb-Sn alloy. Oral mucous membrane irritation test was performed to evaluate the surface biological properties of the Ti-Zr-Nb-Sn alloy. The results suggested that the surface hardness and wear-resistant properties of the Ti-12.5Zr-3Nb-2.5Sn alloy were superior to commercially pure Ti. The oral mucous irritation test showed that all samples had no mucous membrane irritation. It indicates that Ti-12.5Zr-3Nb-2.5Sn has large potential to be used as dental restoration material.

  1. Biological Characteristics of Experimental Genotype Mixtures of Cydia Pomonella Granulovirus (CpGV: Ability to Control Susceptible and Resistant Pest Populations

    Directory of Open Access Journals (Sweden)

    Benoit Graillot

    2016-05-01

    Full Text Available The detection of resistance in codling moth (Cydia pomonella populations against the Mexican isolate of its granulovirus (CpGV-M, raised questions on the sustainability of the use of this biological insecticide. In resistant host cells, CpGV-M is not able to complete its replication cycle because replication is blocked at an early step. Virus isolates able to overcome this resistance have been characterized—among them, the CpGV-R5 isolate. In mixed infections on resistant insects, both CpGV-M and CpGV-R5 viruses replicate, while CpGV-M alone does not induce mortality. Genetically heterogeneous virus populations, containing 50% of each CpGV-M and CpGV-R5 appear to control resistant host populations as well as CpGV-R5 alone at the same final concentration, even if the concentration of CpGV-R5 is only half in the former. The use of mixed genotype virus preparations instead of genotypically homogeneous populations may constitute a better approach than traditional methods for the development of baculovirus-based biological insecticides.

  2. Biological Characteristics of Experimental Genotype Mixtures of Cydia Pomonella Granulovirus (CpGV): Ability to Control Susceptible and Resistant Pest Populations.

    Science.gov (United States)

    Graillot, Benoit; Bayle, Sandrine; Blachere-Lopez, Christine; Besse, Samantha; Siegwart, Myriam; Lopez-Ferber, Miguel

    2016-05-21

    The detection of resistance in codling moth (Cydia pomonella) populations against the Mexican isolate of its granulovirus (CpGV-M), raised questions on the sustainability of the use of this biological insecticide. In resistant host cells, CpGV-M is not able to complete its replication cycle because replication is blocked at an early step. Virus isolates able to overcome this resistance have been characterized-among them, the CpGV-R5 isolate. In mixed infections on resistant insects, both CpGV-M and CpGV-R5 viruses replicate, while CpGV-M alone does not induce mortality. Genetically heterogeneous virus populations, containing 50% of each CpGV-M and CpGV-R5 appear to control resistant host populations as well as CpGV-R5 alone at the same final concentration, even if the concentration of CpGV-R5 is only half in the former. The use of mixed genotype virus preparations instead of genotypically homogeneous populations may constitute a better approach than traditional methods for the development of baculovirus-based biological insecticides.

  3. Biological Characteristics of Experimental Genotype Mixtures of Cydia Pomonella Granulovirus (CpGV): Ability to Control Susceptible and Resistant Pest Populations.

    Science.gov (United States)

    Graillot, Benoit; Bayle, Sandrine; Blachere-Lopez, Christine; Besse, Samantha; Siegwart, Myriam; Lopez-Ferber, Miguel

    2016-01-01

    The detection of resistance in codling moth (Cydia pomonella) populations against the Mexican isolate of its granulovirus (CpGV-M), raised questions on the sustainability of the use of this biological insecticide. In resistant host cells, CpGV-M is not able to complete its replication cycle because replication is blocked at an early step. Virus isolates able to overcome this resistance have been characterized-among them, the CpGV-R5 isolate. In mixed infections on resistant insects, both CpGV-M and CpGV-R5 viruses replicate, while CpGV-M alone does not induce mortality. Genetically heterogeneous virus populations, containing 50% of each CpGV-M and CpGV-R5 appear to control resistant host populations as well as CpGV-R5 alone at the same final concentration, even if the concentration of CpGV-R5 is only half in the former. The use of mixed genotype virus preparations instead of genotypically homogeneous populations may constitute a better approach than traditional methods for the development of baculovirus-based biological insecticides. PMID:27213431

  4. Insects resistance bioassay and insecticide penetration biology%昆虫抗药性测定与杀虫剂穿透生物学

    Institute of Scientific and Technical Information of China (English)

    杨健; 王真; 姚安庆

    2011-01-01

    论文阐明了杀虫剂穿透生物学的基本概念及其对昆虫抗药性测定的指导意义;论述了杀虫剂穿透生物学提出的背景及其与"田间毒理学"的关系,分析了在昆虫抗药性生物测定中存在的问题及其主要原因;提出了杀虫剂穿透生物学在昆虫抗药性测定中的应用原则.%This paper sets out the basic concepts of pesticide penetration biology and the determination of insect resistance. The main problems of resistance in insect bioassays are discussed with reference to the principles of pesticide penetration biology.

  5. Synergistic and Additive Effect of Oregano Essential Oil and Biological Silver Nanoparticles against Multidrug-Resistant Bacterial Strains

    OpenAIRE

    Scandorieiro, Sara; de Camargo, Larissa C.; Lancheros, Cesar A. C.; Yamada-Ogatta, Sueli F.; Celso V Nakamura; de Oliveira, Admilton G.; Andrade, Célia G.T. de J.; Duran, Nelson; Nakazato, Gerson; Renata K. T. Kobayashi

    2016-01-01

    Bacterial resistance to conventional antibiotics has become a clinical and public health problem, making therapeutic decisions more challenging. Plant compounds and nanodrugs have been proposed as potential antimicrobial alternatives. Studies have shown that oregano (Origanum vulgare) essential oil (OEO) and silver nanoparticles have potent antibacterial activity, also against multidrug-resistant strains; however, the strong organoleptic characteristics of OEO and the development of resistanc...

  6. MOLECULAR BIOLOGICAL EVIDENCES FOR THE GENETIC STABILITY OF DOXORUBICIN RESISTANT CELL LINE S-180R IN VIVO

    Institute of Scientific and Technical Information of China (English)

    Zheng Guoqiang; Han Fusheng; Zhang Tingjun; Zhan Maocheng; Chen Xiangling; Xu Guangwei

    1998-01-01

    Objective: In order to assess the genetic stability of doxorubicin resistance sarcoma S-180R cell line in vivo.Methods: The drug resistant genes and molecules were examined by flow cytometry, Southern blot, Northern blot and RT-PCR. Results: The results showed that drugefflux in S-180R increased nearly 100-folds, as compared with its parent cells, the rate of half peak width resistant cell/peak high decreased from 0.56 to 0.23 measured by flow cytometry after two years. The mdr1 gene amplified and overexpressed significantly in S-180R and the expression of topoisomerase Ⅱα gene decreased remarkably in S-180R. There was no significant different of the MRP expression between S-180R and S-180.Conclusion: These results indicated that drug resistance of S-180R was maintained and also increased. The major mechanism of drug resistance is the amplification and overexpression of mdr1 gene, the decreased expression of topoisomerase Ⅱα also contributed to it. So, S-180R is an ideal experimental model for the study of doxorubicin resistance and its reversion in vivo.

  7. Metabolomic Profiling of the Effects of Melittin on Cisplatin Resistant and Cisplatin Sensitive Ovarian Cancer Cells Using Mass Spectrometry and Biolog Microarray Technology

    Directory of Open Access Journals (Sweden)

    Sanad Alonezi

    2016-10-01

    Full Text Available In the present study, liquid chromatography-mass spectrometry (LC-MS was employed to characterise the metabolic profiles of two human ovarian cancer cell lines A2780 (cisplatin-sensitive and A2780CR (cisplatin-resistant in response to their exposure to melittin, a cytotoxic peptide from bee venom. In addition, the metabolomics data were supported by application of Biolog microarray technology to examine the utilisation of carbon sources by the two cell lines. Data extraction with MZmine 2.14 and database searching were applied to provide metabolite lists. Principal component analysis (PCA gave clear separation between the cisplatin-sensitive and resistant strains and their respective controls. The cisplatin-resistant cells were slightly more sensitive to melittin than the sensitive cells with IC50 values of 4.5 and 6.8 μg/mL respectively, although the latter cell line exhibited the greatest metabolic perturbation upon treatment. The changes induced by melittin in the cisplatin-sensitive cells led mostly to reduced levels of amino acids in the proline/glutamine/arginine pathway, as well as to decreased levels of carnitines, polyamines, adenosine triphosphate (ATP and nicotinamide adenine dinucleotide (NAD+. The effects on energy metabolism were supported by the data from the Biolog assays. The lipid compositions of the two cell lines were quite different with the A2780 cells having higher levels of several ether lipids than the A2780CR cells. Melittin also had some effect on the lipid composition of the cells. Overall, this study suggests that melittin might have some potential as an adjuvant therapy in cancer treatment.

  8. Using biological and physico-chemical test methods to assess the role of concrete mixture design in resistance to microbially induced corrosion

    Science.gov (United States)

    House, Mitchell Wayne

    Concrete is the most widely used material for construction of wastewater collection, storage, and treatment infrastructure. The chemical and physical characteristics of hydrated portland cement make it susceptible to degradation under highly acidic conditions. As a result, some concrete wastewater infrastructure may be susceptible to a multi-stage degradation process known as microbially induced corrosion, or MIC. MIC begins with the production of aqueous hydrogen sulfide (H2S(aq)) by anaerobic sulfate reducing bacteria present below the waterline. H2S(aq) partitions to the gas phase where it is oxidized to sulfuric acid by the aerobic sulfur oxidizing bacteria Thiobacillus that resides on concrete surfaces above the waterline. Sulfuric acid then attacks the cement paste portion of the concrete matrix through decalcification of calcium hydroxide and calcium silica hydrate coupled with the formation of expansive corrosion products. The attack proceeds inward resulting in reduced service life and potential failure of the concrete structure. There are several challenges associated with assessing a concrete's susceptibility to MIC. First, no standard laboratory tests exist to assess concrete resistance to MIC. Straightforward reproduction of MIC in the laboratory is complicated by the use of microorganisms and hydrogen sulfide gas. Physico-chemical tests simulating MIC by immersing concrete specimens in sulfuric acid offer a convenient alternative, but do not accurately capture the damage mechanisms associated with biological corrosion. Comparison of results between research studies is difficult due to discrepancies that can arise in experimental methods even if current ASTM standards are followed. This thesis presents two experimental methods to evaluate concrete resistance to MIC: one biological and one physico-chemical. Efforts are made to address the critical aspects of each testing method currently absent in the literature. The first method presented is a new test

  9. Comparison of Chemical Sensitivity of Fresh and Long-Stored Heat Resistant Neosartorya fischeri Environmental Isolates Using BIOLOG Phenotype MicroArray System.

    Directory of Open Access Journals (Sweden)

    Jacek Panek

    Full Text Available Spoilage of heat processed food and beverage by heat resistant fungi (HRF is a major problem for food industry in many countries. Neosartorya fischeri is the leading source of spoilage in thermally processed products. Its resistance to heat processing and toxigenicity makes studies about Neosartorya fischeri metabolism and chemical sensitivity essential. In this study chemical sensitivity of two environmental Neosartorya fischeri isolates were compared. One was isolated from canned apples in 1923 (DSM3700, the other from thermal processed strawberry product in 2012 (KC179765, used as long-stored and fresh isolate, respectively. The study was conducted using Biolog Phenotype MicroArray platforms of chemical sensitivity panel and traditional hole-plate method. The study allowed for obtaining data about Neosartorya fischeri growth inhibitors. The fresh isolate appeared to be much more resistant to chemical agents than the long-stored isolate. Based on phenotype microarray assay nitrogen compounds, toxic cations and membrane function compounds were the most effective in growth inhibition of N. fischeri isolates. According to the study zaragozic acid A, thallium(I acetate and sodium selenate were potent and promising N. fischeri oriented fungicides which was confirmed by both chemical sensitivity microplates panel and traditional hole-plate methods.

  10. Polyether ionophores: broad-spectrum and promising biologically active molecules for the control of drug-resistant bacteria and parasites

    Science.gov (United States)

    Kevin, Dion A; Meujo, Damaris AF; Hamann, Mark T

    2016-01-01

    Background As multidrug-resistant (MDR) pathogens continue to emerge, there is a substantial amount of pressure to identify new drug candidates. Carboxyl polyethers, also referred to as polyether antibiotics, are a unique class of compounds with outstanding potency against a variety of critical infectious disease targets including protozoa, bacteria and viruses. The characteristics of these molecules that are of key interest are their selectivity and high potency against several MDR etiological agents. Objective Although many studies have been published about carboxyl polyether antibiotics, there are no recent reviews of this class of drugs. The purpose of this review is to provide the reader with an overview of the spectrum of activity of polyether antibiotics, their mechanism of action, toxicity and potential as drug candidates to combat drug-resistant infectious diseases. Conclusion Polyether ionophores show a high degree of promise for the potential control of drug-resistant bacterial and parasitic infections. Despite the long history of use of this class of drugs, very limited medicinal chemistry and drug optimization studies have been reported, thus leaving the door open to these opportunities in the future. Scifinder and PubMed were the main search engines used to locate articles relevant to the topic presented in the present review. Keywords used in our search were specific names of each of the 88 compounds presented in the review as well as more general terms such as polyethers, ionophores, carboxylic polyethers and polyether antibiotics. PMID:23480512

  11. Resistance to Aspergillus flavus in maize and peanut:Molecular biology, breeding, environmental stress,and future perspectives

    Institute of Scientific and Technical Information of China (English)

    Jake; C.Fountain; Pawan; Khera; Liming; Yang; Spurthi; N.Nayak; Brian; T.Scully; Robert; D.Lee; Zhi-Yuan; Chen; Robert; C.Kemerait; Rajeev; K.Varshney; Baozhu; Guo

    2015-01-01

    The colonization of maize(Zea mays L.) and peanut(Arachis hypogaea L.) by the fungal pathogen Aspergillus flavus results in the contamination of kernels with carcinogenic mycotoxins known as aflatoxins leading to economic losses and potential health threats to humans. The regulation of aflatoxin biosynthesis in various Aspergillus spp. has been extensively studied, and has been shown to be related to oxidative stress responses. Given that environmental stresses such as drought and heat stress result in the accumulation of reactive oxygen species(ROS) within host plant tissues, host-derived ROS may play an important role in cross-kingdom communication between host plants and A. flavus. Recent technological advances in plant breeding have provided the tools necessary to study and apply knowledge derived from metabolomic, proteomic, and transcriptomic studies in the context of productive breeding populations. Here, we review the current understanding of the potential roles of environmental stress, ROS, and aflatoxin in the interaction between A.flavus and its host plants, and the current status in molecular breeding and marker discovery for resistance to A. flavus colonization and aflatoxin contamination in maize and peanut. We will also propose future directions and a working model for continuing research efforts linking environmental stress tolerance and aflatoxin contamination resistance in maize and peanut.

  12. Resistance to Aspergillus flavus in maize and peanut:Molecular biology, breeding, environmental stress, and future perspectives

    Institute of Scientific and Technical Information of China (English)

    Jake C. Fountain; Baozhu Guo; Pawan Khera; Liming Yang; Spurthi N. Nayak; Brian T. Scully; Robert D. Lee; Zhi-Yuan Chen; Robert C. Kemerait; Rajeev K. Varshney

    2015-01-01

    The colonization of maize (Zea mays L.) and peanut (Arachis hypogaea L.) by the fungal pathogen Aspergillus flavus results in the contamination of kernels with carcinogenic mycotoxins known as aflatoxins leading to economic losses and potential health threats to humans. The regulation of aflatoxin biosynthesis in various Aspergillus spp. has been extensively studied, and has been shown to be related to oxidative stress responses. Given that environmental stresses such as drought and heat stress result in the accumulation of reactive oxygen species (ROS) within host plant tissues, host-derived ROS may play an important role in cross-kingdom communication between host plants and A. flavus. Recent technological advances in plant breeding have provided the tools necessary to study and apply knowledge derived from metabolomic, proteomic, and transcriptomic studies in the context of productive breeding populations. Here, we review the current understanding of the potential roles of environmental stress, ROS, and aflatoxin in the interaction between A. flavus and its host plants, and the current status in molecular breeding and marker discovery for resistance to A. flavus colonization and aflatoxin contamination in maize and peanut. We will also propose future directions and a working model for continuing research efforts linking environmental stress tolerance and aflatoxin contamination resistance in maize and peanut.

  13. Impacts of off-road vehicles on nitrogen cycles in biological soil crusts: Resistance in different U.S. deserts

    Science.gov (United States)

    Belnap, J.

    2002-01-01

    Biological soil crusts are an important component of desert ecosystems, as they influence soil stability and fertility. This study examined and compared the short-term vehicular impacts on lichen cover and nitrogenase activity (NA) of biological soil crusts. Experimental disturbance was applied to different types of soil in regions throughout the western U.S. (Great Basin, Colorado Plateau, Sonoran, Chihuahuan, and Mojave deserts). Results show that pre-disturbance cover of soil lichens is significantly correlated with the silt content of soils, and negatively correlated with sand and clay. While disturbance appeared to reduce NA at all sites, differences were statistically significant at only 12 of the 26 sites. Cool desert sites showed a greater decline than hot desert sites, which may indicate non-heterocystic cyanobacterial species are more susceptible to disturbance than non-heterocystic species. Sandy soils showed greater reduction of NA as sand content increased, while fine-textured soils showed a greater decline as sand content increased. At all sites, higher NA before the disturbance resulted in less impact to NA post-disturbance. These results may be useful in predicting the impacts of off-road vehicles in different regions and different soils. ?? 2002 Published by Elsevier Science Ltd.

  14. EFSA BIOHAZ Panel (EFSA Panel on Biological Hazards), 2013. Scientific Opinion on Carbapenem resistance in food animal ecosystems

    DEFF Research Database (Denmark)

    Hald, Tine; Baggesen, Dorte Lau

    -1-encoding genes were located on IncHI2 plasmids. A methodology including selective culture is proposed for the detection of CP strains of Enterobacteriaceae and Acinetobacter spp. The choice of selective media for the surveillance of carbapenem resistance for testing animal and food samples needs...... to be experimentally evaluated and validated. Biochemical and phenotypic tests for the confirmatory identification of CP bacteria are available. For CP bacteria in animals and food, active/passive monitoring and/or targeted surveys should cover key zoonotic agents, animal pathogens and indicator organisms. Priority......Carbapenems are broad-spectrum β-lactam antimicrobials used for the treatment of serious infections in humans. To date only sporadic studies have reported the occurrence of carbapenemase-producing (CP) bacteria in food-producing animals and their environment. The bacteria and enzymes isolated...

  15. Radiocomplexation and biological evaluation of nemonoxacin in mice infected with multiresistant Staphylococcus aureus and penicillin-resistant Streptococci

    International Nuclear Information System (INIS)

    In the current investigation nemonoxacin (NMX) was radiolabeled with 99mTc in the presence of stannous chloride dihydrate as reducing agent. Factors affecting the percent labeling yield of 99mTc-Nemonoxacin (99mTc-NMX) complex were studied in details. The labeled compound was radiochemically characterized and was stable for a time up to 4 h. The complex showed in vitro saturated binding with living multiresistant Staphylococcus aureus (MRSA) and penicillin-resistant Streptococci (PRSC). Biodistribution and imaging studies were performed. All results showed that 99mTc-NMX complex is a promising agent for MRSA and PRSC infection imaging and can differentiate between infected and sterile inflammations. (author)

  16. Radiolabeling, biological evaluation and molecular docking of delafloxacin. A novel methicillin-resistant Staphylococcus aureus infection radiotracer

    International Nuclear Information System (INIS)

    Labeling of delafloxacin with technetium-99m (99mTc) and its characterization in terms of in vitro stability and in vitro binding with methicillin-resistant Staphylococcus aureus (MRSA) were explored. Optimum amounts of reactants were 2.5 mg delafloxacin, 125 µg stannous chloride dihydrate and ∼125 MBq pertechnetate. The 99mTc-delafloxacin was stable up to 6 h. Molecular modeling and docking studies showed that the complex will stabilize the DNA-topoisomerase IIA cleavage complex and inhibit strands separation. The in vivo evaluation showed highest specific accumulation in the live MRSA model (8 %) compared to other models. All gathered data supported the usefulness of 99mTc-delafloxacin as a MRSA radiotracer. (author)

  17. Multifunctional commercially pure titanium for the improvement of bone integration: Multiscale topography, wettability, corrosion resistance and biological functionalization.

    Science.gov (United States)

    Ferraris, Sara; Vitale, Alessandra; Bertone, Elisa; Guastella, Salvatore; Cassinelli, Clara; Pan, Jinshan; Spriano, Silvia

    2016-03-01

    The objects of this research are commercially pure titanium surfaces, with multifunctional behavior, obtained through a chemical treatment and biological functionalization. The explored surfaces are of interest for dental implants, in contact with bone, where several simultaneous and synergistic actions are needed, in order to get a fast and effective osseointegration. The here described modified surfaces present a layer of titanium oxide, thicker than the native one, with a multi-scale surface topography (a surface roughness on the nano scale, which can be overlapped to a micro or macro roughness of the substrate) and a high density of OH groups, that increase surface wettability, induce a bioactive behavior (hydroxyapatite precipitation in simulated body fluid) and make possible the grafting of biomolecules (alkaline phosphatase, ALP, in the present research). The surface oxide is an efficient barrier against corrosion, with passive behavior both with and without application of an external voltage.

  18. Design, synthesis and biological evaluation of LBM-A5 derivatives as potent P-glycoprotein-mediated multidrug resistance inhibitors.

    Science.gov (United States)

    Wu, Yuxiang; Pan, Miaobo; Dai, Yuxuan; Liu, Baomin; Cui, Jian; Shi, Wei; Qiu, Qianqian; Huang, Wenlong; Qian, Hai

    2016-05-15

    A novel series of P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) inhibitors with triazol-N-phenethyl-tetrahydroisoquinoline or triazol-N-ethyl-tetrahydroisoquinoline scaffold were designed and synthesized via click chemistry. Most of the synthesized compounds showed higher reversal activity than verapamil (VRP). Among them, the most potent compound 4 showed a comparable activity with the known potent P-gp inhibitor WK-X-34 with lower cytotoxicity toward K562 cells (IC50>100μM). Compared with VRP, compound 4 exhibited more potency in increasing drug accumulation in K562/A02 MDR cells. Moreover, compound 4 could significantly reverse MDR in a dose-dependent manner and also persist longer chemo-sensitizing effect than VRP with reversibility. Further mechanism studies revealed that compound 4 could remarkably increase the intracellular accumulation of Adriamycin (ADM) in K562/A02 cells as well as inhibit rhodamine-123 (Rh123) efflux from the cells. These results suggested that compound 4 may represent a promising candidate for developing P-gp-mediated MDR inhibitors. PMID:27073052

  19. Skeletal muscle fiber type: using insights from muscle developmental biology to dissect targets for susceptibility and resistance to muscle disease.

    Science.gov (United States)

    Talbot, Jared; Maves, Lisa

    2016-07-01

    Skeletal muscle fibers are classified into fiber types, in particular, slow twitch versus fast twitch. Muscle fiber types are generally defined by the particular myosin heavy chain isoforms that they express, but many other components contribute to a fiber's physiological characteristics. Skeletal muscle fiber type can have a profound impact on muscle diseases, including certain muscular dystrophies and sarcopenia, the aging-induced loss of muscle mass and strength. These findings suggest that some muscle diseases may be treated by shifting fiber type characteristics either from slow to fast, or fast to slow phenotypes, depending on the disease. Recent studies have begun to address which components of muscle fiber types mediate their susceptibility or resistance to muscle disease. However, for many diseases it remains largely unclear why certain fiber types are affected. A substantial body of work has revealed molecular pathways that regulate muscle fiber type plasticity and early developmental muscle fiber identity. For instance, recent studies have revealed many factors that regulate muscle fiber type through modulating the activity of the muscle regulatory transcription factor MYOD1. Future studies of muscle fiber type development in animal models will continue to enhance our understanding of factors and pathways that may provide therapeutic targets to treat muscle diseases. WIREs Dev Biol 2016, 5:518-534. doi: 10.1002/wdev.230 For further resources related to this article, please visit the WIREs website. PMID:27199166

  20. Design, Synthesis, and Biological and Structural Evaluations of Novel HIV-1 Protease Inhibitors To Combat Drug Resistance

    Energy Technology Data Exchange (ETDEWEB)

    Parai, Maloy Kumar; Huggins, David J.; Cao, Hong; Nalam, Madhavi N.L.; Ali, Akbar; Schiffer, Celia A.; Tidor, Bruce; Rana, Tariq M. (MIT); (UMASS, MED); (Sanford-Burnham)

    2012-09-11

    A series of new HIV-1 protease inhibitors (PIs) were designed using a general strategy that combines computational structure-based design with substrate-envelope constraints. The PIs incorporate various alcohol-derived P2 carbamates with acyclic and cyclic heteroatomic functionalities into the (R)-hydroxyethylamine isostere. Most of the new PIs show potent binding affinities against wild-type HIV-1 protease and three multidrug resistant (MDR) variants. In particular, inhibitors containing the 2,2-dichloroacetamide, pyrrolidinone, imidazolidinone, and oxazolidinone moieties at P2 are the most potent with Ki values in the picomolar range. Several new PIs exhibit nanomolar antiviral potencies against patient-derived wild-type viruses from HIV-1 clades A, B, and C and two MDR variants. Crystal structure analyses of four potent inhibitors revealed that carbonyl groups of the new P2 moieties promote extensive hydrogen bond interactions with the invariant Asp29 residue of the protease. These structure-activity relationship findings can be utilized to design new PIs with enhanced enzyme inhibitory and antiviral potencies.

  1. Radiocomplexation and biological characterization of the 99mTcN-trovafloxacin dithiocarbamate. A novel methicillin-resistant Staphylococcus aureus infection imaging agent

    International Nuclear Information System (INIS)

    The radiolabeling of trovafloxacin dithiocarbamate (TVND) with technetium-99m using [99mTc-N]2+ core was investigated and biologically assessed as prospective infection imaging agent. The achievability of the 99mTcN-TVND complex as a future MRSA infection radiotracer was investigated in artificially methicillin-resistant Staphylococcus aureus (MRSA) infected male Sprague-Dawley rats (MSDR). Radiochemically the 99mTcN-TVND complex was characterized in terms of radiochemical purity (RCP) in saline, in vitro permanence in serum, in vitro binding with MRSA and biodistribution in living and heat killed MRSA infected MSDR. Radiochemically the complex showed stability in saline with a 97.90 ± 0.22% yield and serum at 37 deg C up to 4 h. The 99mTcN-TVND complex showed saturated in vitro binding with MRSA. Normal in vivo uptake in the MRSA infected MDRS was observed with a five fold uptake in the infected muscle as compared to inflamed and normal muscles. The high RCP values, in vitro permanence in serum, better in vitro binding with MRSA, biodistribution behavior and the target to non-target (infected to inflamed muscle) ratios posed the 99mTcN-TVND complex as a promising MRSA infection radiotracer. (author)

  2. Prevalence of methicillin-resistant staphylococci isolated from different biological samples at Policlinico Umberto I of Rome: correlation with vancomycin susceptibility

    Directory of Open Access Journals (Sweden)

    Maria Teresa Mascellino

    2011-03-01

    Full Text Available The methicillin-resistance is increasing all over the world in the last decade. It is more frequent among coagulase-negative staphylococci (MRCoNS; infact the 52% of S. epidermidis strains results to be resistant to methicillin.The methicillin-resistant strains also show a reduced sensitivity towards the first-line agents such as glycopeptides and other antibiotics commonly used in therapy such as trimethoprim-sulphamethoxazole, imipenem, gentamycin, fosfomycin and chlarytromicin. Unlike MRSA (Methicillin-resistant S. aureus, MRCoNS resistance to glycopeptides generally concerns teicoplanin. Although vancomycin resistance is rare in Staphylococcus isolates, the detected shift towards higher values of MICs might affect patient’s clinical outcome.

  3. EFFECT ON BIOLOGICAL BEHAVIOR OF CHEMOTHERAPY-RESISTANT TUMOR CELLS BY HUMAN WILD-TYPE P53, GM-CSF AND B7-1 GENES VIA RECOMBINANT ADENOVIRUS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To explore the effect on biological behavior of chemotherapy-resistant tumor cells by human wild-type p53, GM-CSF and B7-1 genes mediated via recombinant adenovirus. Methods: p53-abnormal KB-v200 (VCR resistant) and KB-s (VCR sensitive) cell lines were used as model tumor cells, which are resistant and sensitive to chemotherapeutic drugs respectively. After infected with recombinant adenovirus carrying human wild-type p53, GM-CSF and B7-1 genes, changes in biological behavior (including drug sensitivity) of these two kinds of gene-transduced cancer cells were observed. Results: Both of the cell lines were susceptible to adenovirus, all of three exogenous genes (p53, GM-CSF and B7-1) could be effectively expressed in these cell lines, their growth was suppressed, and apoptosis was induced. The drug-pumping-out function of Pgp glycoprotein on the cytomembrane of drug-resistant KB-v200 cells was markedly affected 48h after transfection of the recombinant adenovirus, revealed by increase of the amount of rhodamine 123 accumulation in the cells. The MTT assay also indicated the reversal of their sensitivity to VCR drugs. In vivo experiment in nude mice it was demonstrated reduction of tumorigenicity of the KB-v200 cells or KB-s cells infected with the recombinant adenovirus, and increase of their sensitivity to VCR. Conclusion: The clinical application of this recombinant adenovirus carrying agents might be more effective in treatment of tumors with multidrug resistance (MDR).

  4. Biological and Epidemiological Features of Antibiotic-Resistant Streptococcus pneumoniae in Pre- and Post-Conjugate Vaccine Eras: a United States Perspective.

    Science.gov (United States)

    Kim, Lindsay; McGee, Lesley; Tomczyk, Sara; Beall, Bernard

    2016-07-01

    Streptococcus pneumoniae inflicts a huge disease burden as the leading cause of community-acquired pneumonia and meningitis. Soon after mainstream antibiotic usage, multiresistant pneumococcal clones emerged and disseminated worldwide. Resistant clones are generated through adaptation to antibiotic pressures imposed while naturally residing within the human upper respiratory tract. Here, a huge array of related commensal streptococcal strains transfers core genomic and accessory resistance determinants to the highly transformable pneumococcus. β-Lactam resistance is the hallmark of pneumococcal adaptability, requiring multiple independent recombination events that are traceable to nonpneumococcal origins and stably perpetuated in multiresistant clonal complexes. Pneumococcal strains with elevated MICs of β-lactams are most often resistant to additional antibiotics. Basic underlying mechanisms of most pneumococcal resistances have been identified, although new insights that increase our understanding are continually provided. Although all pneumococcal infections can be successfully treated with antibiotics, the available choices are limited for some strains. Invasive pneumococcal disease data compiled during 1998 to 2013 through the population-based Active Bacterial Core surveillance program (U.S. population base of 30,600,000) demonstrate that targeting prevalent capsular serotypes with conjugate vaccines (7-valent and 13-valent vaccines implemented in 2000 and 2010, respectively) is extremely effective in reducing resistant infections. Nonetheless, resistant non-vaccine-serotype clones continue to emerge and expand. PMID:27076637

  5. Biological parameters of two strains (acaricide resistant and susceptible of the tick Rhipicephalus microplusParâmetros biológicos de duas cepas (sensível e resistente a acaricidas do carrapato Rhipicephalus microplus

    Directory of Open Access Journals (Sweden)

    Luciana Dalla Rosa

    2013-10-01

    Full Text Available The resistance of Rhipicephalus microplus to acaricides occurs in almost all regions where it is present and treatments with chemicals are the most frequent. Therefore the monitoring of ticks is crucial to diagnose resistance at an early stage to help slow down the spread of resistance and to obtain knowledge of the distribution of acaricide resistance. The objective of the present work was to know the biological parameters of R. microplus sensitive strain to the main acaricides used. We compared the number and weight of engorged females, as well as the mass of eggs obtained the percentage of hatching and reproductive efficiency of two strains (acaricide-resistant and susceptible of the tick R. microplus, after passage in cattle. The results showed a reduced capacity to adjust the acaricide-susceptible strain, which presented the lowest number of ticks recovered (p?0.0001, with less weight and egg mass. With respect to reproductive parameters, the ticks susceptible strain showed hatching rate eggs (p=0.0002410 and reproductive efficiency reduced when compared with those of the acaricide-resistant strain. A resistência do Rhipicephalus microplus aos carrapaticidas ocorre em quase todas as regiões onde ele está presente e os tratamentos com produtos químicos são os mais frequentes. Portanto, monitoramento de carrapatos é fundamental para diagnosticar a resistência em um estágio inicial, diminuir a propagação e obter conhecimento da distribuição da resistência acaricida. Com o objetivo de se conhecer os parâmetros biológicos de uma cepa sensível de R. microplus aos principais carrapaticidas utilizados, o presente trabalho foi desenvolvido. Foram comparados o número e o peso de teleóginas, assim como a massa de ovos obtida, a percentagem de eclosão e a eficiência reprodutiva de duas cepas (sensível e resistente a acaricidas do carrapato R. microplus, após passagem em bovinos. Os resultados demonstraram uma menor capacidade de

  6. Challenges and advances in systems biology analysis of Bacillus spore physiology; molecular differences between an extreme heat resistant spore forming Bacillus subtilis food isolate and a laboratory strain

    NARCIS (Netherlands)

    Brul, S.; Beilen, J.van; Caspers, M.; O'Brien, A.; Koster, C.de; Oomes, S.; Smelt, J.; Kort, R.; Beek, A.ter

    2011-01-01

    Bacterial spore formers are prime organisms of concern in the food industry. Spores from the genus Bacillus are extremely stress resistant, most notably exemplified by high thermotolerance. This sometimes allows surviving spores to germinate and grow out to vegetative cells causing food spoilage and

  7. Biological Threats

    Science.gov (United States)

    ... Workplace Plans School Emergency Plans Main Content Biological Threats Biological agents are organisms or toxins that can ... for Disease Control and Prevention . Before a Biological Threat Unlike an explosion, a biological attack may or ...

  8. Synthetic Biology for Therapeutic Applications

    OpenAIRE

    Abil, Zhanar; Xiong, Xiong; Zhao, Huimin

    2014-01-01

    Synthetic biology is a relatively new field with the key aim of designing and constructing biological systems with novel functionalities. Today, synthetic biology devices are making their first steps in contributing new solutions to a number of biomedical challenges, such as emerging bacterial antibiotic resistance and cancer therapy. This review discusses some synthetic biology approaches and applications that were recently used in disease mechanism investigation and disease modeling, drug d...

  9. 番茄灰霉病菌对咯菌腈的抗性诱变及抗药突变体的生物学特性%Induced mutation of Botrytis cinerea resistant to fludioxonil and biological characteristics of resistant mutants

    Institute of Scientific and Technical Information of China (English)

    纪军建; 张小风; 王文桥

    2012-01-01

    为评估番茄灰霉病菌Botrytis cinerea对咯菌腈的抗性风险,就室内经紫外照射获得抗药突变体的方法及抗性突变体的生物学性状进行了研究.结果表明:番茄灰霉病菌分生孢子的紫外照射亚致死时间为90 ~120 s;经亚致死时间紫外照射后,4个亲本菌株中有2个菌株共产生了6个抗咯菌腈的突变体,其EC50值是亲本菌株的310倍以上,抗性突变频率为3.13×10-7;经紫外照射诱变获得的所有抗性突变体在菌丝生长速率、产孢量、产菌核能力及其在番茄果实上的致病性方面均比其亲本菌株明显降低.相关分析显示,所得抗咯菌腈突变体对氟啶胺、啶菌(噁)唑、啶酰菌胺和嘧霉胺无交互抗性.表明番茄灰霉病菌对咯菌腈的抗药性风险较低.%To assess the resistance risk of Botrytis cinerea to fludioxonil, the method for fludioxonil resistance mutagenesis and the biological characteristics of resistant mutants were studied. The results showed that the sub-lethal UV irradiation time for the conidia of B. Cinerea was 90-120 seconds. Four wild sensitive parental isolates were irradiated for sub-lethal time by UV, and six resistant mutants were obtained from two parental isolates. The ratio of EC50 value of resistant mutants comparing with that of its parental strain was more than 310 times,the frequency of resistance mutation was 3. 13×10-7. The mycelial growth rate, sporulation, sclerotia production and pathogenicity of resistant mutants decreased significantly as compared with their parental isolates. The analysis showed that the mutants had no cross resistance to other fungicides that have different mechanisms. The above results indicated that B. Cinerea on tomato had low risk of resistance to fludioxonil.

  10. Biological and Clinical Study of 6-Deoxy-6-Iodo-D-Glucose: a iodinated tracer of glucose transport and of insulin-resistance in human

    International Nuclear Information System (INIS)

    Insulin resistance (IR), characterized by a depressed cellular sensitivity to insulin in insulin-sensitive organs, is a central feature to obesity, the metabolic syndrome, and diabetes mellitus and leads to increase cardiovascular diseases, particularly heart failure. All these events are today serious public health problems. But actually, there is no simple tool to measure insulin resistance. The gold standard technique remains the hyperinsulinemic euglycemic clamp. However, the complexity and length of this technique render it unsuitable for routine clinical use. Many methods or index have been proposed to assess insulin resistance in human, but none have shown enough relevance to be used in clinical use. The U1039 INSERM unit previously has validated a new tracer of glucose transport, radiolabelled with 123 iodine and has developed a fast and simple imaging protocol with a small animal gamma camera, which allows the obtaining of an IR index for each organ, showing more discriminating for the heart. The project of my thesis was the human transfer of this measurement technique, perfectly validated in animal. The first part of this thesis evaluated to tolerance, in vivo kinetics, distribution and dosimetry of novel tracer of glucose transport, the [123I]-6DIG. The safeties of new tracer and measurement technique were adequate. There were no adverse effects with excellent tolerance of the whole protocol. 6DIG eliminating was fast, primarily in the urine and complete within 72 h. The effective whole-body absorbed dose for a complete scan with injection of 92.5 * 2 MBq was between 3 to 4 mSv. The second part of this thesis evaluated in human feasibility and reproducibility of the measurement technique validated in animal. The third part showed techniques used to allow human transfer of this method. The study protocol was applied on 12 subjects (healthy volunteers (n=6) and type 2 diabetic patients (n=6)). With a method adapted to measure in humans, we determined an IR

  11. Synthesis of new steroidal inhibitors of P-glycoprotein-mediated multidrug resistance and biological evaluation on K562/R7 erythroleukemia cells.

    Science.gov (United States)

    de Ravel, Marc Rolland; Alameh, Ghina; Melikian, Maxime; Mahiout, Zahia; Emptoz-Bonneton, Agnès; Matera, Eva-Laure; Lomberget, Thierry; Barret, Roland; Rocheblave, Luc; Walchshofer, Nadia; Beltran, Sonia; El Jawad, Lucienne; Mappus, Elisabeth; Grenot, Catherine; Pugeat, Michel; Dumontet, Charles; Le Borgne, Marc; Cuilleron, Claude Yves

    2015-02-26

    A simple route for improving the potency of progesterone as a modulator of P-gp-mediated multidrug resistance was established by esterification or etherification of hydroxylated 5α/β-pregnane-3,20-dione or 5β-cholan-3-one precursors. X-ray crystallography of representative 7α-, 11α-, and 17α-(2'R/S)-O-tetrahydropyranyl ether diastereoisomers revealed different combinations of axial-equatorial configurations of the anomeric oxygen. Substantial stimulation of accumulation and chemosensitization was observed on K562/R7 erythroleukemia cells resistant to doxorubicin, especially using 7α,11α-O-disubstituted derivatives of 5α/β-pregnane-3,20-dione, among which the 5β-H-7α-benzoyloxy-11α-(2'R)-O-tetrahydropyranyl ether 22a revealed promising properties (accumulation index 2.9, IC50 0.5 μM versus 1.2 and 10.6 μM for progesterone), slightly overcoming those of verapamil and cyclosporin A. Several 7α,12α-O-disubstituted derivatives of 5β-cholan-3-one proved even more active, especially the 7α-O-methoxymethyl-12α-benzoate 56 (accumulation index 3.8, IC50 0.2 μM). The panel of modulating effects from different O-substitutions at a same position suggests a structural influence of the substituent completing a simple protection against stimulating effects of hydroxyl groups on P-gp-mediated transport.

  12. Variations in grain lipophilic phytochemicals, proteins and resistance to Fusarium spp. growth during grain storage as affected by biological plant protection with Aureobasidium pullulans (de Bary).

    Science.gov (United States)

    Wachowska, Urszula; Tańska, Małgorzata; Konopka, Iwona

    2016-06-16

    Modern agriculture relies on an integrated approach, where chemical treatment is reduced to a minimum and replaced by biological control that involves the use of active microorganisms. The effect of the antagonistic yeast-like fungus Aureobasidium pullulans on proteins and bioactive compounds (alkylresorcinols, sterols, tocols and carotenoids) in winter wheat grain and on the colonization of wheat kernels by fungal microbiota, mainly Fusarium spp. pathogens, was investigated. Biological treatment contributed to a slight increase contents of tocols, alkylresorcinols and sterols in grain. At the same time, the variation of wheat grain proteins was low and not significant. Application of A. pullulans enhanced the natural yeast colonization after six months of grain storage and inhibited growth of F. culmorum pathogens penetrating wheat kernel. This study demonstrated that an integrated approach of wheat grain protection with the use of the yeast-like fungus A. pullulans reduced kernel colonization by Fusarium spp. pathogens and increased the content of nutritionally beneficial phytochemicals in wheat grain without a loss of gluten proteins responsible for baking value. PMID:27055191

  13. Synthesis of new steroidal inhibitors of P-glycoprotein-mediated multidrug resistance and biological evaluation on K562/R7 erythroleukemia cells.

    Science.gov (United States)

    de Ravel, Marc Rolland; Alameh, Ghina; Melikian, Maxime; Mahiout, Zahia; Emptoz-Bonneton, Agnès; Matera, Eva-Laure; Lomberget, Thierry; Barret, Roland; Rocheblave, Luc; Walchshofer, Nadia; Beltran, Sonia; El Jawad, Lucienne; Mappus, Elisabeth; Grenot, Catherine; Pugeat, Michel; Dumontet, Charles; Le Borgne, Marc; Cuilleron, Claude Yves

    2015-02-26

    A simple route for improving the potency of progesterone as a modulator of P-gp-mediated multidrug resistance was established by esterification or etherification of hydroxylated 5α/β-pregnane-3,20-dione or 5β-cholan-3-one precursors. X-ray crystallography of representative 7α-, 11α-, and 17α-(2'R/S)-O-tetrahydropyranyl ether diastereoisomers revealed different combinations of axial-equatorial configurations of the anomeric oxygen. Substantial stimulation of accumulation and chemosensitization was observed on K562/R7 erythroleukemia cells resistant to doxorubicin, especially using 7α,11α-O-disubstituted derivatives of 5α/β-pregnane-3,20-dione, among which the 5β-H-7α-benzoyloxy-11α-(2'R)-O-tetrahydropyranyl ether 22a revealed promising properties (accumulation index 2.9, IC50 0.5 μM versus 1.2 and 10.6 μM for progesterone), slightly overcoming those of verapamil and cyclosporin A. Several 7α,12α-O-disubstituted derivatives of 5β-cholan-3-one proved even more active, especially the 7α-O-methoxymethyl-12α-benzoate 56 (accumulation index 3.8, IC50 0.2 μM). The panel of modulating effects from different O-substitutions at a same position suggests a structural influence of the substituent completing a simple protection against stimulating effects of hydroxyl groups on P-gp-mediated transport. PMID:25634041

  14. Resistance-resistant antibiotics.

    Science.gov (United States)

    Oldfield, Eric; Feng, Xinxin

    2014-12-01

    New antibiotics are needed because drug resistance is increasing while the introduction of new antibiotics is decreasing. We discuss here six possible approaches to develop 'resistance-resistant' antibiotics. First, multitarget inhibitors in which a single compound inhibits more than one target may be easier to develop than conventional combination therapies with two new drugs. Second, inhibiting multiple targets in the same metabolic pathway is expected to be an effective strategy owing to synergy. Third, discovering multiple-target inhibitors should be possible by using sequential virtual screening. Fourth, repurposing existing drugs can lead to combinations of multitarget therapeutics. Fifth, targets need not be proteins. Sixth, inhibiting virulence factor formation and boosting innate immunity may also lead to decreased susceptibility to resistance. Although it is not possible to eliminate resistance, the approaches reviewed here offer several possibilities for reducing the effects of mutations and, in some cases, suggest that sensitivity to existing antibiotics may be restored in otherwise drug-resistant organisms.

  15. Study on the biological resistance of Lactobacillus acidophilus%嗜酸乳杆菌生物抗性的研究

    Institute of Scientific and Technical Information of China (English)

    程秀云; 罗玉芳

    2011-01-01

    A fine strain of Lactobacillus acidophilus was selected as the research object. It measured the method of plate culture count to confirm the survival of Lactobacillus acidophilus under different factors to study its acidresistant, osmotic pressure tolerance, salt and bile tolerance and to study the comprehensive influences of gastric acid, salt and bile on Lactobacillus acidophilus by simulating of human gastrointestinal environment. Finally it concluded that Lactobacillus acidophilus had a certain resistance capacity.%选择一株嗜酸乳杆菌优良菌株为研究对象,用平板菌落计数法测定嗜酸乳杆菌在各因素的作用下的存活率来研究其耐酸、耐渗透压、耐胆盐能力以及模拟人体肠胃环境研究胃酸、食盐、胆盐对嗜酸乳杆菌的综合影响;从实验结果得出嗜酸乳杆菌具有一定的抗性能力.

  16. Synthesis of the 99mTc(CO)3-trovafloxacin dithiocarbamate complex and biological characterization in artificially methicillin-resistant Staphylococcus aureus infected rats model

    International Nuclear Information System (INIS)

    Synthesis of the 99mTc(CO)3-trovafloxacin dithiocarbamate (99mTc(CO)3-TVND) complex and biological characterization in artificially Staphylococcus aureus (S. aureus) infected rats model was assessed. The suitability of the complex was evaluated and compared with 99mTcN-TVND, in terms of radiochemical immovability in saline, in vitro permanence in serum, in vitro binding with S. aureus and biodistribution in Male Sprague-Dawley rats (MSDR). After 30 min of the reconstitution both the complexes showed maximum radiochemical stabilities in saline and remain more than 90% stable up to 120 min. However the 99mTc(CO)3-TVND showed to some extent higher stability than 99mTcN-TVND complex. In serum 1.75% less de-tagging was observed than 99mTcN-TVND complex. Both the complexes showed saturated in vitro binding with S. aureus and no significant difference were observed between the uptakes. Six fold uptakes were noted in the infected muscle as compared to the inflamed and normal muscles of the MDSR. The uptake of the 99mTc(CO)3-TVND in infected muscle of the MSDR was 2.25% high as compared to the 99mTcN-TVND complex. Based on radiochemical stabilities in saline, serum, in vitro binding with MRSA and significantly higher uptake in the infected muscle, we recommend both the complexes for in vivo investigation of the MRSA infection in human. (author)

  17. Genetic differentiation among Maruca vitrata F. (Lepidoptera: Crambidae populations on cultivated cowpea and wild host plants: implications for insect resistance management and biological control strategies.

    Directory of Open Access Journals (Sweden)

    Tolulope A Agunbiade

    Full Text Available Maruca vitrata Fabricius (Lepidoptera: Crambidae is a polyphagous insect pest that feeds on a variety of leguminous plants in the tropics and subtropics. The contribution of host-associated genetic variation on population structure was investigated using analysis of mitochondrial cytochrome oxidase 1 (cox1 sequence and microsatellite marker data from M. vitrata collected from cultivated cowpea (Vigna unguiculata L. Walp., and alternative host plants Pueraria phaseoloides (Roxb. Benth. var. javanica (Benth. Baker, Loncocarpus sericeus (Poir, and Tephrosia candida (Roxb.. Analyses of microsatellite data revealed a significant global FST estimate of 0.05 (P≤0.001. The program STRUCTURE estimated 2 genotypic clusters (co-ancestries on the four host plants across 3 geographic locations, but little geographic variation was predicted among genotypes from different geographic locations using analysis of molecular variance (AMOVA; among group variation -0.68% or F-statistics (FSTLoc = -0.01; P = 0.62. These results were corroborated by mitochondrial haplotype data (φSTLoc = 0.05; P = 0.92. In contrast, genotypes obtained from different host plants showed low but significant levels of genetic variation (FSTHost = 0.04; P = 0.01, which accounted for 4.08% of the total genetic variation, but was not congruent with mitochondrial haplotype analyses (φSTHost = 0.06; P = 0.27. Variation among host plants at a location and host plants among locations showed no consistent evidence for M. vitrata population subdivision. These results suggest that host plants do not significantly influence the genetic structure of M. vitrata, and this has implications for biocontrol agent releases as well as insecticide resistance management (IRM for M. vitrata in West Africa.

  18. Genetic differentiation among Maruca vitrata F. (Lepidoptera: Crambidae) populations on cultivated cowpea and wild host plants: implications for insect resistance management and biological control strategies.

    Science.gov (United States)

    Agunbiade, Tolulope A; Coates, Brad S; Datinon, Benjamin; Djouaka, Rousseau; Sun, Weilin; Tamò, Manuele; Pittendrigh, Barry R

    2014-01-01

    Maruca vitrata Fabricius (Lepidoptera: Crambidae) is a polyphagous insect pest that feeds on a variety of leguminous plants in the tropics and subtropics. The contribution of host-associated genetic variation on population structure was investigated using analysis of mitochondrial cytochrome oxidase 1 (cox1) sequence and microsatellite marker data from M. vitrata collected from cultivated cowpea (Vigna unguiculata L. Walp.), and alternative host plants Pueraria phaseoloides (Roxb.) Benth. var. javanica (Benth.) Baker, Loncocarpus sericeus (Poir), and Tephrosia candida (Roxb.). Analyses of microsatellite data revealed a significant global FST estimate of 0.05 (P≤0.001). The program STRUCTURE estimated 2 genotypic clusters (co-ancestries) on the four host plants across 3 geographic locations, but little geographic variation was predicted among genotypes from different geographic locations using analysis of molecular variance (AMOVA; among group variation -0.68%) or F-statistics (FSTLoc = -0.01; P = 0.62). These results were corroborated by mitochondrial haplotype data (φSTLoc = 0.05; P = 0.92). In contrast, genotypes obtained from different host plants showed low but significant levels of genetic variation (FSTHost = 0.04; P = 0.01), which accounted for 4.08% of the total genetic variation, but was not congruent with mitochondrial haplotype analyses (φSTHost = 0.06; P = 0.27). Variation among host plants at a location and host plants among locations showed no consistent evidence for M. vitrata population subdivision. These results suggest that host plants do not significantly influence the genetic structure of M. vitrata, and this has implications for biocontrol agent releases as well as insecticide resistance management (IRM) for M. vitrata in West Africa.

  19. 防御素的生物学特性及其抗病基因工程%Biological characteristics of defensin and its disease-resistance genetic engineering

    Institute of Scientific and Technical Information of China (English)

    付蓝宝; 于嘉林; 刘伟华

    2011-01-01

    防御素是一种富含半胱氨酸的小分子多肽,对细菌等微生物具有广谱抗性,且作用机制特殊.迄今为止,国内外在防御素方面进行了大量的研究,已经从各类生物体中分离出不同种类的防御素.并在基因工程和医药领域呈现广泛的应用前景.文章对防御素的分类、生物学特性,包括哺乳动物α-、β-、θ-防御素、昆虫以及植物防御素的分子结构及抗菌活性进行了综述,阐述了防御素的膜作用及与细胞内复合物结合的作用机制.总结和归纳了防御素基因的分离、表达研究进展及动、植物防御素基因在抗病基因工程领域的应用,并对防御素在未来的生物制药和植物抗病基因工程方面的应用前景进行了展望.%Defensin is a kind of cysteine-rich small peptide, which has a broad spectrum of resistance to bacteria with a special resistance mechanism.So far, a large number of studies on defensins have been reported, and the different types of defensins have been isolated from various organisms.A broad prospect of application on defensins has been displayed both in genetic engineering and medicine field.This article reviewed the classification and the biological characteristics of defensins, including mammalian α-, β-, θ-defensins, insect defensins, and plant defensins.The molecular structures,antibacterial activities, and antibacterial mechanisms of these definsins were summarized.The two mechanisms of defensin, including independent membrane mechanism and targeting of intracellular compounds by defensins, are expounded.This paper also summarized the researches on isolation and expression of defensin genes and disease resistance genetic engineering of mammal and plant defensins.A prospect of the future applications of defensin both in biopharmaceutical sciences and plant disease resistance genetic engineering was discussed.

  20. Establishment of human glioblastoma multiform multidrug resistant cell line in vitro and identification of its biological characteristics%人脑胶质瘤多药耐药细胞株的构建及生物学特性鉴定

    Institute of Scientific and Technical Information of China (English)

    白义凤; 廖红展; 刘天助; 郭洪波

    2011-01-01

    Objective To establish the imatinib (STI-571)-resistant subline in vitro and investigate its biological characteristics. Methods Human glioblastoma multiform drug-resistant cell line (named U251AR) was established in vitro by successively increasing the concentration of imatinib in a cell culture medium. The 50% inhibitory dose (IC50) values and the resistance indexes ([IC50U251/STI-571]/[IC50 U251]) for other chemotherapeutic agents were evaluated using cell counting kit-8 assays. Expressions of acquired multidrug resistance P-glycoprotein (MDR 1, ABCB 1; MDR3, ABCB4),breast cancer resistance protein (BCRP, ABCG2) and multidrug resistance-associated protein 1 (MRP1,ABCC1) were detected by QRT-PCR. Flow cytometry was employed to detect the protein expression of ABCG2. Results The U251AR was developed after culture for 12 months and similar morphologies of U251 and U251/STI-571 cells were determined. The resistance coefficient of U251AR cells to imatinib was 20.41 times more than that of the parent cells, and U251AR cells showed cross-resistance to many anti-tumor agents (P<0.05). The resistance coefficients of U251AR cell line to doxorubicin and cisplatin were 5.06 and 10.28 times, respectively, more than those of U251 cells (P<0.05). QRT-PCR indicated that the mRNA levels of MDR1, MRP1, BCRPandABCB4 (P-g4) in the U251/STI571 resistant cells were significantly higher than those in the U251 cells (P<0.05). The protein expression of ABCG2 in U251AR cell line was significantly increased as compared with that in the parent cells (P<0.05).Conclusion We have successfully established multidrug resistant cell line U251AR, and the drug resistance of U251/STI571 is associated with over-expressions of ABCC1, ABCB1, ABCB4, and ABCG2 mRNA, and ABCG2 protein.%目的 体外构建胶质瘤耐甲磺酸伊玛替尼多药耐药细胞株,并研究其生物学特性。方法采用逐渐增加培养基中伊玛替尼药物浓度的方法诱导构建耐甲磺酸

  1. 人肺腺癌紫杉醇耐药细胞系的建立及生物学特性研究%Establishment and biological characteristics of Taxol-induced drug resistant human lung adenocarcinoma cell line

    Institute of Scientific and Technical Information of China (English)

    张广亮; 钱晓萍; 刘宝瑞; 胡静; 刘芹; 张一凡; 禹立霞

    2013-01-01

    目的 探讨紫杉醇(Taxol)诱导的人肺腺癌细胞A549耐药细胞系A549/Taxol生物学特性和耐药机制.方法 采用Taxol浓度递增间歇诱导法,建立A549/Taxol细胞系,MTT法测定耐药性,流式细胞术检测细胞周期,Transwell小室法检测细胞侵袭力,荧光定量RTPCR检测乳腺癌易感基因1(BRCA1)、受体相关蛋白80(RAP80)、微管相关蛋白T(Tau)、多药耐药基因1(MDR1)mRNA表达水平.结果 A549/Taxol细胞对Taxol及多西紫杉醇均有耐药性,对前者耐药性更强(RI=48.36 vs.27.21)(P<0.01).与A549细胞相比,A549/Taxol细胞G1期的细胞比例增加[(50.56±0.25)% vs.(57.75±0.16)%],而S期细胞比例减少[(37.85±1.48)% vs.(30.21±1.87)%],细胞凋亡率增加幅度减小[(56.43±1.12)% vs.(9.23±1.18)%],细胞侵袭力增强[(38.6±9.97)个vs.(116.8±21.73)个],BRCA1、RAP80 mRNA表达降低,而MDR1、Tau mRNA表达显著升高(P<0.01).结论 成功建立Taxol耐药细胞系A549/Taxol,有助于进一步研究肺癌耐药机制.%Objective To explore the biological characteristics and mechanisms of drug resistance in Taxol-induced drug resistant human lung adenocarcinoma cell line (A549/Taxol). Methods The cell line A549/Taxol was established by intermittent-inducing method of gradually increasing the concentration of Taxol in vitro. Its drug resistance, cell cycle and cell invasion were detected by MTT assay, flow cytometry and transwell chamber, respectively. The expressions of BRCAl,RAP80,Tau and MDR1 mRNA were measured by quantitative RT-PCR. Results The cell line A549/Taxol was resistant to both Taxol and Docetaxel, which was more resistant to Taxol than that to Docetaxel(RI=48. 36 vs. 27. 21)(P<0. 01). Compared with cell line A549,in cell line A549/ Taxol,G1 phase cell fraction increased [(50. 56±0. 25)% vs. (57. 75 ± 0. 16)%],S phase cell fraction decreased[(37. 85 ± 1. 48)% vs. (30. 21 ± 1. 87)%],the increase in apoptosis rate was smaller[(56. 43 ± 1. 12)% vs. (9. 23 ± 1

  2. Perplexities of treatment resistence in eating disorders

    OpenAIRE

    Halmi, Katherine A.

    2013-01-01

    Background Treatment resistance is an omnipresent frustration in eating disorders. Attempts to identify the features of this resistance and subsequently develop novel treatments have had modest effects. This selective review examines treatment resistant features expressed in core eating disorder psychopathology, comorbidities and biological features. Novel treatments addressing resistance are discussed. Description The core eating disorder psychopathology of anorexia nervosa becomes a coping ...

  3. Biological computation

    CERN Document Server

    Lamm, Ehud

    2011-01-01

    Introduction and Biological BackgroundBiological ComputationThe Influence of Biology on Mathematics-Historical ExamplesBiological IntroductionModels and Simulations Cellular Automata Biological BackgroundThe Game of Life General Definition of Cellular Automata One-Dimensional AutomataExamples of Cellular AutomataComparison with a Continuous Mathematical Model Computational UniversalitySelf-Replication Pseudo Code Evolutionary ComputationEvolutionary Biology and Evolutionary ComputationGenetic AlgorithmsExample ApplicationsAnalysis of the Behavior of Genetic AlgorithmsLamarckian Evolution Genet

  4. Alteração das características biológicas dos biótipos de azevém (Lolium multiflorum ocasionada pela resistência ao herbicida glyphosate Change in the biological characteristics of ryegrass (Lolium multiflorum biotypes caused by resistance to the herbicide glyphosate

    Directory of Open Access Journals (Sweden)

    L. Vargas

    2005-03-01

    accumulation by the biotype were assessed. In the second experiment different rates of glyphosate and grass herbicides were tested: glyphosate, haloxyfop-r, diclofop, fluazifop-p, fenoxaprop-p and paraquat. A third experiments was carried out under glasshouse conditions to determine the curve of dry matter accumulation. The results showed GR50 of 287.5 and 4,833.5 g e. a. ha-1 of glyphosate for the sensitive and resistant biotypes, respectively. The results showed that the resistant factor (RF was 16.8 and that the resistance mechanism alters the biological characteristics of the resistant biotype affecting its sensitivity to grass herbicides.

  5. 儿童呼吸道感染流感嗜血杆菌的生物学分型及耐药性%Biology grouping and drug resistance of Haemophilus influenzae from respiratory tract infection in children

    Institute of Scientific and Technical Information of China (English)

    王运中; 季伟; 陶云珍; 吾金彪; 丁云芳

    2012-01-01

    目的 了解苏州地区呼吸道感染患儿感染流感嗜血杆菌(HI)的生物型分布及耐药性.方法 用负压吸取呼吸道分泌物进行培养,对HI进行生物学分型,头孢硝噻酚检测其β-内酰胺酶,并采用纸片法进行药敏试验.结果 获得HI 154株,生物型以Ⅱ型和Ⅲ型为主,占分离总数的81.2%.Ⅱ、Ⅲ、Ⅶ型在各季节的检出率差异明显(P<0.05).各型产β-内酰胺酶分别为Ⅰ型33.3%、Ⅱ型41.7%、Ⅲ型32.3%、Ⅶ型35.7%、Ⅷ型25.0%.HI对氨苄西林耐药率为35.7%,其多重耐药率为22.7%;且主要为产β-内酰胺酶株.结论 苏州地区儿童感染HI以生物型Ⅱ型和Ⅲ型为主,且以Ⅱ型产酶率最高;HI耐药形势越来越严峻.%Objective To investigate the distribution of biotype and drug resistance of Haemophilus influenzae(HI) from respiratory tract infection in children in Suzhou district, China. Methods Respiratory tract secretions for culture was obtained by vacuum suction and biology grouping was done for the isolation of HI The beta-lactamase of HI was detected by nitrocefin and drug resistance was tested by Kirby-Bauer disc method. Results A total of 154 strains of HI was isolated,among which biotypes of Ⅱ and Ⅲ were the two most common ones, and accounted for 81. 2%. There was a significant season difference of the detection rate for biotypes of Ⅱ , Ⅲ and Ⅶ (P<0. 05). The beta-lactamase positive rate was 33. 3% for biotype I ,41. 7% for biotypeII ,32. 3% for biotype Ⅲ, 35. 7% for biotype Ⅶ and 25. 0% for biotype Ⅷ The resistance rate of HI to ampicillin was 35. 7% and the muti-resistance rate of HI was 22. 7% .mainly producing beta-lactamase of HL Conclusion The biotypes of Ⅱand Ⅲ are the main common types in Suzhou district The beta-lactamase positive rate of biotype Ⅱ is the highest one. The situation of drug resistence of HI has been serious day by day.

  6. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... En Español Search FDA Submit search Popular Content Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, ... Biologics Animal & Veterinary Cosmetics Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of ...

  7. Study on the molecular biology of cefoxitin-resistant Klebsiella pneumoniae strains%头孢西丁耐药的肺炎克雷伯菌分子生物学研究

    Institute of Scientific and Technical Information of China (English)

    栾英; 贺飞; 李桂玲; 何昕; 多丽波

    2011-01-01

    Objective To investigate the molecular biology of one cefoxitin-resistant Klebsiela pneumoniae strain. Methods AmpC and AmpR genes of one cefoxitin-resistant Klebsiella pneumoniae were analyzed by PCR, and then the pET22b( + )-AmpR expression plasmid and expression strain were constructed. Results A 1 140 bp segment of AmpC and a 876 bp segment of AmpR were cloned. These sequences showed that recombinant AmpC and AmpR genes were highly identical to those of Morganella morganii. Fusion protein about 34 kD was expressed by E. coli BI21 ( DE3 ) transfected with recombinant plasmid pET22b ( + )-AmpR.Conclusion There are regulator AmpR genes in plasmid of cefoxitin-resistant Klebsiella pneunoniae isolates. AmpR genes express AmpR fusion protein. Induced resistance mechanism is also found in plasmid-mediated AmpC β-lactamase.%目的 检测本院分离的对头孢西丁耐药的肺炎克雷伯菌分子生物学特点.方法 以本院临床分离的一株对头孢西丁耐药的肺炎克雷伯菌为研究对象,采用聚合酶链反应(PCR),分别用特异性引物进行AmpC酶全编码基因及AmpR 调节基因的扩增,并且构建pET-22b(+)-AmpR的表达质粒和表达菌株.结果 PCR分别扩增出约1 140 bp和876 bpDNA片段,经测序证实,1 140 bp的序列与摩根摩根菌染色体上AmpC酶全长编码基因同源性达99.1%,876 bp的序列与摩根摩根菌染色体上AmpR 基因同源性达98%.重组质粒pET-22b(+)-AmpR转化E.coli BL21(DE3)后表达融合蛋白的相对分子量为34 kD,与预期分子量相符.结论 对头孢西丁耐药的肺炎克雷伯菌质粒上存在调控因子AmpR,能够表达AmpR蛋白,诱导性耐药机制同样存在于质粒介导的AmpCβ-内酰胺酶中.

  8. Isolation and biological characteristics of phages of carbapenem-resistant Acinetobacter baumannii%耐碳青霉烯类鲍曼不动杆菌噬菌体的分离鉴定及其生物学特性

    Institute of Scientific and Technical Information of China (English)

    张劼; 罗永艾

    2012-01-01

    Objective To investigate the biological characteristics of phages of carbapenem-resistant Acinetobacter baumannii ( CRAB), and provide new strategy for controlling CRAB infection. Methods Phages of CRAB isolated from raw sewage of a hospital were identified using the plaque method. The morphology of phages was observed by electron microscopy. The genome of phages was extracted for electrophoresis. The structural proteins of phages were analysed by SDS-PAGE. The optimal multiplicity of infection, resistant mutation rate and one-step growth curve of phages were determined. Results One CRAB-specific and tailless phage with double-stranded DNA was isolated, and was named as phage AB3. The size of phage AB3 genome was about 35 kb, and the relative molecular mass of major coat protein was 35 x 10 . The incubation and burst periods of phage AB3 were 20 min and 60 min respectively, the burst size was 350, and the mutation rate of phage resistance was 2.5 × 10-10 . The phage AB3 was stable to a wide range of pH and temperature. Conclusion Phage AB3 has relatively broad host range, shorter incubation period, apparent burst size, lower resistant mutation rate and good stability to physical and chemical factors, which leads to its promising prospect in clinical application.%目的 通过分离耐碳青霉烯类鲍曼小动杆菌(CRAB)噬菌体,研究其生物学特性,为噬菌体治疗CRAB感染提供实验依据.方法 利用噬菌斑法从医院污水中分离CRAB噬菌体,电子显微镜观察噬菌体的形态特征,提取其基因组行酶切电泳,SDSPAGE分析噬菌体表面衣壳蛋白,测定噬菌体感染复数和耐受突变率,并观察其一步生长曲线.结果 筛选出1株具有较宽裂解谱的无尾双链DNA的CRAB噬菌体,命名为噬菌体AB3.其基因组大小约35 kb,表面主要衣壳蛋白相对分子质量约为35×103.该噬菌体感染宿主菌的潜伏期为20 min,爆发期为60 min,裂解量为350,耐受突变率为2.5×10-10,对pH值耐受

  9. Drug Resistance

    Science.gov (United States)

    HIV Treatment Drug Resistance (Last updated 3/1/2016; last reviewed 3/1/2016) Key Points As HIV multiplies in the ... the risk of drug resistance. What is HIV drug resistance? Once a person becomes infected with HIV, ...

  10. Antibiotic Resistance

    Science.gov (United States)

    ... lives. But there is a growing problem of antibiotic resistance. It happens when bacteria change and become able ... resistant to several common antibiotics. To help prevent antibiotic resistance Don't use antibiotics for viruses like colds ...

  11. Biologically resistant contaminants, primary treatment with ozone

    Energy Technology Data Exchange (ETDEWEB)

    Echegaray, Diego F. [White Martins Gases Industriais do Nordeste S.A., Salvador, BA (Brazil); Olivieri, Nadja F. [White Martins Gases Industriais S.A., Cordovil, RJ (Brazil)

    1993-12-31

    Organic effluent oxidation tests were conducted in petrochemical companies, in Camacari Petrochemical Complex (Northeast Brazil), to reduce treatment costs and improve the primary treatment efficiency in each industrial process. Ozone achieved 99.96 percent benzene reduction and 100 percent ethyl benzene and toluene reduction. Process efficiency is strongly dependent on the wastewater chemical composition and concentration. For this reason it is necessary to run pilot trials for each specific case. Ozone was obtained feeding commercial oxygen through a corona discharge generator and dissolved in the effluent with a bubble column. Commercial oxygen was used instead of air to increase 250 percent the ozone production, using the same ozone generator. (author). 4 figs., 2 tabs.

  12. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  13. Biology Notes.

    Science.gov (United States)

    School Science Review, 1982

    1982-01-01

    Presents procedures, exercises, demonstrations, and information on a variety of biology topics including labeling systems, biological indicators of stream pollution, growth of lichens, reproductive capacity of bulbous buttercups, a straw balance to measure transpiration, interaction of fungi, osmosis, and nitrogen fixation and crop production. (DC)

  14. Biological characteristics and drug resistance of Eimeria tenella Shijiazhuang strain%柔嫩艾美耳球虫石家庄株的生物学特性与抗药性研究

    Institute of Scientific and Technical Information of China (English)

    李蕴玉; 李佩国; 张香斋; 张艳英; 张文香; 贾青辉; 陈娟

    2012-01-01

    用5×104个柔嫩艾美耳球虫石家庄株孢子化卵囊感染14日龄雏鸡,对卵囊潜隐期、最早孢子化时间、形态及大小等生物学特性进行了测定。并以最适抗球虫活性百分率(POAA)、病变记分减少率(RLS)、相对卵囊产量(ROP)和抗球虫指数(ACI)为指标,检测了常用抗球虫药对其敏感性。结果表明:(1)该虫株寄生于盲肠,呈宽卵圆形,壁光滑,分2层,多数可见极粒。卵囊大小范围为(19.68~27.76)μm×(15.21~23.99)μm,平均大小为(23.41±2.22)μm×(19.34±2.27)μm,卵囊指数1.21。孢子囊大小范围为(8.30~14.28)μm×(4.05~9.15)μm,平均大小为(11.69±1.53)μm×(6.74±1.26)μm,孢子囊指数1.73。潜隐期和最短孢子化时间分别为133h和20h。(2)该虫株对马杜霉素、克球粉与球敌呈完全抗药性;对瑞冠球呈轻度抗药性;而对氨丙啉和金三特无抗药性。%Each chicken of 14-old-day was orally infected with 5×104 sporulated oocysts of Eimeria tenella Shijiazhuang strain,and some biological characteristics such as oocyst shape,size,prepaten period and the minimum sporulation time were detected.At the same time,based on the criteria of the percent of optimum anticoccidial activity(POAA),reduction of lesion scores(RLS),relative oocyst production(ROP) and anticoccidial index(ACI),the sensitivities of the strain to common coccidiostats were tested.The results showed that(1)the oocyst parasitized in caecum and was broadly ovoid with a smooth wall,(23.41±2.22) μm×(19.34±2.27) μm,average(23.41±2.22) μm×(19.34±2.27) μm in size,the shape index was 1.21,sporocyst size was(8.30-14.28) μm×(4.05-9.15) μm,average(11.69±1.53) μm×(6.74±1.26) μm,shape index of sporocyst was 1.73.The prepatent period and the minimum sporulation time was 132 h and 20 h,respectively;(2)the strain was complete resistant to maduramicin

  15. Biological warfare agents

    Directory of Open Access Journals (Sweden)

    Duraipandian Thavaselvam

    2010-01-01

    Full Text Available The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies.

  16. Quantum Biology

    Directory of Open Access Journals (Sweden)

    Alessandro Sergi

    2009-06-01

    Full Text Available A critical assessment of the recent developmentsof molecular biology is presented.The thesis that they do not lead to a conceptualunderstanding of life and biological systems is defended.Maturana and Varela's concept of autopoiesis is briefly sketchedand its logical circularity avoided by postulatingthe existence of underlying living processes,entailing amplification from the microscopic to the macroscopic scale,with increasing complexity in the passage from one scale to the other.Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces,is criticized. It is suggested that the correct interpretationof quantum dispersion forces (van der Waals, hydrogen bonding, and so onas quantum coherence effects hints at the necessity of includinglong-ranged forces (or mechanisms for them incondensed matter theories of biological processes.Some quantum effects in biology are reviewedand quantum mechanics is acknowledged as conceptually important to biology since withoutit most (if not all of the biological structuresand signalling processes would not even exist. Moreover, it is suggested that long-rangequantum coherent dynamics, including electron polarization,may be invoked to explain signal amplificationprocess in biological systems in general.

  17. Ecological Compatibility of GM Crops and Biological Control

    Science.gov (United States)

    Insect-resistant and herbicide-tolerant genetically modified (GM) crops pervade many modern cropping systems, and present challenges and opportunities for developing biologically-based pest management programs. Interactions between biological control agents (insect predators, parasitoids, and pathog...

  18. Quantum Biology

    CERN Document Server

    Sergi, Alessandro

    2009-01-01

    A critical assessment of the recent developments of molecular biology is presented. The thesis that they do not lead to a conceptual understanding of life and biological systems is defended. Maturana and Varela's concept of autopoiesis is briefly sketched and its logical circularity avoided by postulating the existence of underlying {\\it living processes}, entailing amplification from the microscopic to the macroscopic scale, with increasing complexity in the passage from one scale to the other. Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces, is criticized. It is suggested that the correct interpretation of quantum dispersion forces (van der Waals, hydrogen bonding, and so on) as quantum coherence effects hints at the necessity of including long-ranged forces (or mechanisms for them) in condensed matter theories of biological processes. Some quantum effects in biology are reviewed and quantum mechanics is acknowledge...

  19. Biological Oceanography

    Science.gov (United States)

    Abbott, M. R.

    1984-01-01

    Within the framework of global biogeochemical cycles and ocean productivity, there are two areas that will be of particular interest to biological oceanography in the 1990s. The first is the mapping in space time of the biomass and productivity of phytoplankton in the world ocean. The second area is the coupling of biological and physical processes as it affects the distribution and growth rate of phytoplankton biomass. Certainly other areas will be of interest to biological oceanographers, but these two areas are amenable to observations from satellites. Temporal and spatial variability is a regular feature of marine ecosystems. The temporal and spatial variability of phytoplankton biomass and productivity which is ubiquitous at all time and space scales in the ocean must be characterized. Remote sensing from satellites addresses these problems with global observations of mesocale (2 to 20 days, 10 to 200 km) features over a long period of time.

  20. 呼吸道嗜血杆菌属的生物学分型及耐药性分析%Biological typing and drug resistance analysis of Haemophilus strains from respiratory tract

    Institute of Scientific and Technical Information of China (English)

    江秀爱; 赵自云; 姜蓓; 乔显森

    2015-01-01

    目的:了解该院临床分离嗜血杆菌属的季节分布、生物学分型及耐药性。方法收集呼吸道感染患者的痰液和咽拭子,采用手工法、MicSCAN4全自动细菌鉴定分析仪、HNID 鉴定板对分离培养的221株嗜血杆菌进行菌种鉴定,并进行生物学分型。用纸片扩散(K-B)法进行药物敏感试验,采用头孢硝噻吩纸片法进行β-内酰胺酶检测。结果临床分离流感嗜血杆菌96株(占1.6%),生物Ⅰ型10株(10.4%),生物Ⅱ型31株(32.3%),生物Ⅲ型40株(41.7%),其他生物型15株(15.6%)。副流感嗜血杆菌125株(占2.1%),生物Ⅰ型15株(12.0%),生物Ⅱ型23株(18.4%),生物Ⅲ型69株(55.2%),生物Ⅳ型18株(14.4%),未检出其他生物型。冬季感染率最高。流感嗜血杆菌和副流感嗜血杆菌对氨苄西林耐药率分别为40.6%%和44.8%,对复方磺胺甲噁唑的耐药率分别为51.0%和66.4%。流感嗜血杆菌和副流感嗜血杆菌β-内酰胺酶株产酶率分别为40.6%和44.8%,对头孢呋辛、头孢噻肟、美罗培南、氯霉素的敏感率都在90.0%以上。结论呼吸道流感嗜血杆菌和副流感嗜血杆菌感染好发于冬季,感染的生物型均以生物Ⅱ型、Ⅲ型为主,对氨苄西林和复方磺胺甲噁唑的耐药率较高,已不宜用于嗜血杆菌引起感染的经验治疗。对该菌所致呼吸道感染可选用头孢呋辛、头孢噻肟、美罗培南作为治疗的首选药物。%Objective To investigate season distribution,biological typing and drug resistant of Haemophitus in Qingdao Central Hospital.Methods The sputum and throat swab were collected from patients with respiratory tract infection,221 Haemophilus strains were identified and typed by the manual method and MicSCAN4 automatic analyzer,HNID identification plate.Antimicrobial susceptibility was tested by Kirby-Bauer method,and cephalosporins nitrate thiophene paper method was used to detect β-lacta-mase.Results A total of 96

  1. Detection and characterization of mupirocin resistance in Staphylococcus aureus.

    OpenAIRE

    Janssen, D A; Zarins, L T; Schaberg, D R; Bradley, S. F.; Terpenning, M S; Kauffman, C A

    1993-01-01

    Fourteen mupirocin-resistant Staphylococcus aureus strains were isolated over 18 months; 12 exhibited low-level resistance, while two showed high-level resistance. Highly mupirocin-resistant strains contained a large plasmid which transferred mupirocin resistance to other S. aureus strains and to Staphylococcus epidermidis. This plasmid and pAM899-1, a self-transferable gentamicin resistance plasmid, have molecular and biologic similarities.

  2. Biology Notes.

    Science.gov (United States)

    School Science Review, 1981

    1981-01-01

    Outlines a variety of laboratory procedures, techniques, and materials including construction of a survey frame for field biology, a simple tidal system, isolation and applications of plant protoplasts, tropisms, teaching lung structure, and a key to statistical methods for biologists. (DS)

  3. (Biological dosimetry)

    Energy Technology Data Exchange (ETDEWEB)

    Preston, R.J.

    1990-12-17

    The traveler attended the 1st International Conference on Biological Dosimetry in Madrid, Spain. This conference was organized to provide information to a general audience of biologists, physicists, radiotherapists, industrial hygiene personnel and individuals from related fields on the current ability of cytogenetic analysis to provide estimates of radiation dose in cases of occupational or environmental exposure. There is a growing interest in Spain in biological dosimetry because of the increased use of radiation sources for medical and occupational uses, and with this the anticipated and actual increase in numbers of overexposure. The traveler delivered the introductory lecture on Biological Dosimetry: Mechanistic Concepts'' that was intended to provide a framework by which the more applied lectures could be interpreted in a mechanistic way. A second component of the trip was to provide advice with regard to several recent cases of overexposure that had been or were being assessed by the Radiopathology and Radiotherapy Department of the Hospital General Gregorio Maranon'' in Madrid. The traveler had provided information on several of these, and had analyzed cells from some exposed or purportedly exposed individuals. The members of the biological dosimetry group were referred to individuals at REACTS at Oak Ridge Associated Universities for advice on follow-up treatment.

  4. Biology Notes.

    Science.gov (United States)

    School Science Review, 1984

    1984-01-01

    Presents information on the teaching of nutrition (including new information relating to many current O-level syllabi) and part 16 of a reading list for A- and S-level biology. Also includes a note on using earthworms as a source of material for teaching meiosis. (JN)

  5. Network systems biology for targeted cancer therapies

    Institute of Scientific and Technical Information of China (English)

    Ting-Ting Zhou

    2012-01-01

    The era of targeted cancer therapies has arrived.However,due to the complexity of biological systems,the current progress is far from enough.From biological network modeling to structural/dynamic network analysis,network systems biology provides unique insight into the potential mechanisms underlying the growth and progression of cancer cells.It has also introduced great changes into the research paradigm of cancer-associated drug discovery and drug resistance.

  6. Radiation-resistant asporogenic bacteria

    International Nuclear Information System (INIS)

    This paper reports the biological and ecological examinations on the radiation-resistant asporogenic bacteria (mainly concerning Micrococcus radiodurans). Radiation-resistant asporogenic bacteria were isolated from the irradiated areas of the natural world as well as from the general areas and from the Rn waters in the Misasa hot spring. The acquiring of the tolerance to radiation in bacteria was also examined. In addition, the future problems of microbiological treatment with irradiation were mentioned. (Tsukamoto, Y.)

  7. 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.

  8. Inducing Effects and Its Biological Mechanisms of ABA on the Chilling Resistance of Sweet Pepper Seedlings%脱落酸对甜椒幼苗抗寒性的诱导效应及其机理研究

    Institute of Scientific and Technical Information of China (English)

    罗立津; 徐福乐; 翁华钦; 洪淑珠; 段留生; 李召虎

    2011-01-01

    以砂培甜椒幼苗为材料,先用不同浓度脱落酸(ABA)进行灌根处理,再分两组分别于常温(25℃~30℃)生长7 d(常温苗)或低温驯化(10℃~15℃)30 d(驯化苗)之后进行低温胁迫(5℃)处理,分析幼苗的生长状况及其细胞质膜伤害、渗透调节物质、活性氧清除系统、内源激素的变化特征,以探讨脱落酸对甜椒抗寒性的诱导效应及机理.结果显示,(1)各浓度ABA对甜椒常温苗和驯化苗的株高、茎重均无显著影响,但显著促进驯化苗的侧根生长,在低温胁迫下,显著降低驯化苗叶片的呼吸速率;(2)常温苗的相对电导率仅在10 mg/L ABA处理中比对照显著降低,而驯化苗在各处理浓度下均显著降低, MDA含量表现出与此类似的变化;(3)叶片脯氨酸、可溶性糖、可溶性蛋白、钾离子等渗透调节物质含量在各浓度ABA处理常温苗和驯化苗中均有所增加,但仅脯氨酸含量的增加达到显著水平.(4)各浓度ABA处理都一定程度上提高了常温苗的SOD活性,显著降低了常温苗的CAT和POD活性,H2O2积累量均显著降低,但对于驯化苗,1.0 mg/L和10 mg/L ABA处理却显著降低其SOD活性,POD和CAT活性无显著差异,H2O2积累量也无显著变化.(5)茎尖的ZR、JA-Me含量及IAA/ZR、均与对照无显著差异,但IAA、ABA含量、ABA/ZR比值明显提高,其中1.0和10 mg/L处理的内源ABA含量以及10 mg/L处理的ABA/ZR比值显著高于对照.研究表明,脱落酸能通过降低甜椒幼苗呼吸速率,提高叶片脯氨酸、可溶性糖、钾离子等渗透调节物质以及ABA的积累来诱导增强甜椒幼苗的抗寒性,减少活性氧自由基的产生和累积量,从而减轻低温胁迫造成的伤害,且低温驯化条件下比常温下效果更加明显.%To study the inducing effects and biological mechanisms of abscisic acid (ABA) on the chilling resistance of plant,sandy culture method was conducted to examine the effects of ABA on the lipid

  9. Crusts: biological

    Science.gov (United States)

    Belnap, Jayne; Elias, Scott A.

    2013-01-01

    Biological soil crusts, a community of cyanobacteria, lichens, mosses, and fungi, are an essential part of dryland ecosystems. They are critical in the stabilization of soils, protecting them from wind and water erosion. Similarly, these soil surface communities also stabilized soils on early Earth, allowing vascular plants to establish. They contribute nitrogen and carbon to otherwise relatively infertile dryland soils, and have a strong influence on hydrologic cycles. Their presence can also influence vascular plant establishment and nutrition.

  10. Biological programming

    OpenAIRE

    Ramsden, Jeremy J.; Bándi, Gergely

    2010-01-01

    Biology offers a tremendous set of concepts that are potentially very powerfully usable for the software engineer, but they have been barely exploited hitherto. In this position paper we propose a fresh attempt to create the building blocks of a programming technology that could be as successful as life. A key guiding principle is to develop and make use of unambiguous definitions of the essential features of life.

  11. 慢性砷暴露人骨髓间充质干细胞的生物学特性观察%Biological characteristics of arsenic resistance cell chronic arsenic exposure human bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    冉玉琴; 冯丽娜; 徐燕; 唐琪; 慕晓玲

    2010-01-01

    目的 观察抗砷细胞模型慢性砷暴露人骨髓间充质干细胞(CAsE-hFBMSCs)的生物学特性,探讨长期低剂量砷暴露对人骨髓间充质干细胞(hFBMSCs)的影响.方法 常规条件培养hFBMSCs,48 h急性砷毒性实验MTS法检测不同剂量砷刺激条件下[0(对照)、0.25、0.50、1.00、2.00、4.00、8.00、20.00、40.00、80.00、120.00μmol/L]第2代(P2)hFBMSCs细胞生存率,根据检测结果用1.00μmol/L亚砷酸钠刺激hFBMSCs 14周,建立抗砷细胞模型CAsE-hFBMSCs,作为实验组,同时设立对照组,并采用荧光激活细胞分选术鉴定诱导前后细胞表型,流式细胞术检测第2、9、16代(P2、P9、P16)细胞周期,软琼脂克隆形成实验检测细胞是否发生恶性转化.结果 <10μmol/L时,急性砷刺激促进hFBMSCs增殖,而≥10μmol/L时,急性砷刺激则抑制细胞的生长.14周时实验组半数致死剂量(LC_(50))为(89.42±0.64)μmol/L,对照组为(52.48±0.71)μmol/L,组间比较差异有统计学意义(t=123.89,P<0.05);抗砷细胞模型CAsE-hFBMSCs的细胞表型CD34、CD45表达阴性,CD29、CD90、CD166表达阳性,与对照组比较细胞表型未见明显改变;CAsE-hFBMSCs的细胞周期变化较大,与对照组[(8.44±0.45)%、(9.14±0.14)%、(82.42±0.60)%]比较,P2实验组G2/M期[(17.72±5.47)%]和S期细胞[(25.34±3.36)%]增加,G0/G1期细胞减少[(56.96±8.83)%],P16细胞周期恢复至与对照组相近的水平:软琼脂克隆形成实验中,抗砷细胞CAsE-hFBMSCs未见克隆形成.结论 长期低剂量砷刺激对hFBMSCs生物学特性无明显影响.%Objective To study the biological characteristics of arsenic resistance cell model chronic arsenic exposure human bone marrow mesenchymal stem cells (CAsE-hFBMSCs) and discuss the consequence of chronic arsenite exposure to human mesenchymal stem cells (hFBMSCs). Methods hFBMSCs cultivated under general conditions,hFBMSC cell survival rate was detected in 48 hours with arsenite toxicity test under different doses

  12. Marine biology

    International Nuclear Information System (INIS)

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index

  13. Marine biology

    Energy Technology Data Exchange (ETDEWEB)

    Thurman, H.V.; Webber, H.H.

    1984-01-01

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index.

  14. Artful interfaces within biological materials

    Directory of Open Access Journals (Sweden)

    John W.C. Dunlop

    2011-03-01

    Full Text Available Biological materials have a wide range of mechanical properties matching their biological function. This is achieved via complex structural hierarchies, spanning many length scales, arising from the assembly of different sized building blocks during growth. The interfaces between these building blocks can increase resistance to fracture, join materials of different character, make them deform more easily and provide motility. While they represent only a tiny fraction of the overall volume, interfaces are essential for the integrity and function of the overall tissue. Understanding their construction principles, often based on specialized molecular assemblies, may change our current thinking about composite materials.

  15. Camptothecin resistance

    DEFF Research Database (Denmark)

    Brangi, M; Litman, Thomas; Ciotti, M;

    1999-01-01

    but not after camptothecin treatment. In addition to topotecan and SN-38, MXR-overexpressing cells are highly resistant to mitoxantrone and epirubicin. Because these compounds are susceptible to glucuronidation, we examined UDP-glucurono-syltransferase (UGT) activity in parental and resistant cells by TLC...

  16. Anticoagulant Resistance

    DEFF Research Database (Denmark)

    Heiberg, Ann-Charlotte

    specific PCR to verify this genetic form of resistance, but in contrast to animals tested from various surface populations, we could not confirm the Y139C mutation in any of the sewer rats. Our findings could indicate that resistance in surface and sewer population may be caused by different mechanism or...

  17. Antimicrobial Resistance

    Science.gov (United States)

    ... others. For example, the emergence of Plasmodium falciparum multidrug resistance, including resistance to ACTs in the Greater Mekong subregion is an urgent public health concern that is threatening global efforts to reduce the burden of malaria. Although MDR-TB is a growing concern, it is still ...

  18. Biological Databases

    Directory of Open Access Journals (Sweden)

    Kaviena Baskaran

    2013-12-01

    Full Text Available Biology has entered a new era in distributing information based on database and this collection of database become primary in publishing information. This data publishing is done through Internet Gopher where information resources easy and affordable offered by powerful research tools. The more important thing now is the development of high quality and professionally operated electronic data publishing sites. To enhance the service and appropriate editorial and policies for electronic data publishing has been established and editors of article shoulder the responsibility.

  19. Antibiotic Resistance

    DEFF Research Database (Denmark)

    Munck, Christian

    morbidity and mortality as well as an increase in the cost of treatment. Understanding how bacteria respond to antibiotic exposure gives the foundations for a rational approach to counteract antimicrobial resistance. In the work presented in this thesis, I explore the two fundamental sources...... of antimicrobial resistance: (1) adaptive mutations and (2) horizontal acquisition of resistance genes from antibiotic gene reservoirs. By studying the geno- and phenotypic changes of E. coli in response to single and drug-pair exposures, I uncover the evolutionary trajectories leading to adaptive resistance. I...... to rationally design drug combinations that limit the evolution of antibiotic resistance due to counteracting evolutionary trajectories. My results highlight that an in-depth knowledge about the genetic responses to the individual antimicrobial compounds enables the prediction of responses to drug combinations...

  20. Role of Chemotherapy and Mechanisms of Resistance to Chemotherapy in Metastatic Castration-Resistant Prostate Cancer

    Science.gov (United States)

    Lohiya, Vipin; Aragon-Ching, Jeanny B.; Sonpavde, Guru

    2016-01-01

    Chemotherapy using the taxanes, docetaxel and cabazitaxel, remains an important therapeutic option in metastatic castration-resistant prostate cancer (CRPC). However, despite the survival benefits afforded by these agents, the survival increments are modest and resistance occurs universally. Efforts to overcome resistance to docetaxel by combining with biologic agents have heretofore been unsuccessful. Indeed, resistance to these taxanes is also associated with cross-resistance to the antiandrogen drugs, abiraterone and enzalutamide. Here, we discuss the various mechanisms of resistance to chemotherapy in metastatic CRPC and the potential role of emerging regimens and agents in varying clinical phases of development.

  1. Biological biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Jorge-Herrero, E. [Servicio de Cirugia Experimental. Clinica Puerta de Hierro, Madrid (Spain)

    1997-05-01

    There are a number of situations in which substances of biological origin are employed as biomaterials. Most of them are macromolecules derived from isolated connective tissue or the connective tissue itself in membrane form, in both cases, the tissue can be used in its natural form or be chemically treated. In other cases, certain blood vessels can be chemically pretreated and used as vascular prostheses. Proteins such as albumin, collagen and fibrinogen are employed to coat vascular prostheses. Certain polysaccharides have also been tested for use in controlled drug release systems. Likewise, a number of tissues, such as dura mater, bovine pericardium, procine valves and human valves, are used in the preparation of cardiac prostheses. We also use veins from animals or humans in arterial replacement. In none of these cases are the tissues employed dissimilar to the native tissues as they have been chemically modified, becoming a new bio material with different physical and biochemical properties. In short, we find that natural products are being utilized as biomaterials and must be considered as such; thus, it is necessary to study both their chemicobiological and physicomechanical properties. In the present report, we review the current applications, problems and future prospects of some of these biological biomaterials. (Author) 84 refs.

  2. 白僵菌抗多菌灵突变株的诱变及生物学特性研究%INDUCTION AND BIOLOGICAL CHARACTERISTICS OF CARBENDAZIM- RESISTANT MUTANTS OF Beauveria bassiana

    Institute of Scientific and Technical Information of China (English)

    齐永霞; 陈方新; 李增智

    2012-01-01

    The sensitivity and concentration completely inhibited (MIC) of Beauveria bassiana to carbendazim were studied by means of mycelial growth rate method. The results showed that among the tested strains of Beauveria bassiana, Bb06 was the most sensitive to carbendazim, the MIC of Beauveria bassiana to carbendazim was 9μg/ml. The resistant level of the carbendazim-resistant strains of Beauveria bassiana which induced by mycelium and conidia were determined. The results showed that the resistant level of BC-4 was the highest among the carbendazim-resistant strains, and the EC50 and the resistant level were 258. 7711 and 242.11, respectively. The resistance level of BC-3 was the lowest among the carbendazim-resistant strains, and the ECso was 18.6311. The mycelia growth rate and conidia productivity of the carbendazim-resistant strains were also studied. The results showed that the mycelium growth rate of parent strain (Bb06) was the largest(1.78mm/d) and BC-8 was the smallest(1.41mm/d). The conidia productivity of the carbendazim-resistant strains was stronger than the parent strain Bb06. Among the carbendazim-resistant strains, the conidia productivity of BC-4 was the best.%采用菌丝生长速率法测定了球孢白僵菌对多菌灵的敏感性和最低完全抑制浓度(MIC)。结果显示,在供试的球孢白僵菌菌株中,Bb06菌株对多菌灵最敏感,其EC50值为1.0688μg/ml,多菌灵对球孢白僵菌菌丝生长的MIC为9μg/ml。通过菌丝块诱变法和分生孢子诱变法获得球孢白僵菌抗多菌灵突变株,并测定球孢白僵菌不同抗性突变株对多菌灵的抗性水平。结果表明,在抗性突变株中,BC-4菌株的EC50值最大,为258.7711,对多菌灵的抗性水平最高,达到242.11;BC-3菌株的EC50值最小,为18.6311,抗性水平最低。同时对球孢白僵菌抗多菌灵突变株的菌丝生长速率和产孢能力差异的研究表明,Bb06菌株(亲本菌株)的生长速率最大,为1.78mm

  3. Resisting HRD's Resistance to Diversity

    Science.gov (United States)

    Bierema, Laura L.

    2010-01-01

    Purpose: The purpose of this paper is to empirically illustrate how human resource development (HRD) resists and omits issues of diversity in academic programs, textbooks, and research; analyze the research on HRD and diversity over a ten-year period; discuss HRD's resistance to diversity; and offer some recommendations for a more authentic…

  4. Creating biological nanomaterials using synthetic biology

    International Nuclear Information System (INIS)

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems. (review)

  5. Creating biological nanomaterials using synthetic biology

    Directory of Open Access Journals (Sweden)

    MaryJoe K Rice

    2014-01-01

    Full Text Available Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems.

  6. Structural Biology Fact Sheet

    Science.gov (United States)

    ... Home > Science Education > Structural Biology Fact Sheet Structural Biology Fact Sheet Tagline (Optional) Middle/Main Content Area What is structural biology? Structural biology is a field of science focused ...

  7. Simulating Biological and Non-Biological Motion

    Science.gov (United States)

    Bruzzo, Angela; Gesierich, Benno; Wohlschlager, Andreas

    2008-01-01

    It is widely accepted that the brain processes biological and non-biological movements in distinct neural circuits. Biological motion, in contrast to non-biological motion, refers to active movements of living beings. Aim of our experiment was to investigate the mechanisms underlying mental simulation of these two movement types. Subjects had to…

  8. Biological Literacy in a College Biology Classroom.

    Science.gov (United States)

    Demastes, Sherry; Wandersee, James H.

    1992-01-01

    Examines the proposed definition of biological literacy as the understanding of a small number of pervasive biological principles appropriate to making informed personal and societal decisions. Utilizes the content of a major daily newspaper to adjust biology instruction to focus on this notion of biological literacy. Discusses benefits and…

  9. A Brief Introduction to Chinese Biological Biological

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Chinese Biological Abstracts sponsored by the Library, the Shanghai Institutes for Biological Sciences, the Biological Documentation and Information Network, all of the Chinese Academy of Sciences, commenced publication in 1987 and was initiated to provide access to the Chinese information in the field of biology.

  10. Biological hydrogen photoproduction

    Energy Technology Data Exchange (ETDEWEB)

    Nemoto, Y. [Univ. of Miami, FL (United States)

    1995-09-01

    Following are the major accomplishments of the 6th year`s study of biological hydrogen photoproduction which were supported by DOE/NREL. (1) We have been characterizing a biological hydrogen production system using synchronously growing aerobically nitrogen-fixing unicellular cyanobacterium, Synechococcus sp. Miami BG 043511. So far it was necessary to irradiate the cells to produce hydrogen. Under darkness they did not produce hydrogen. However, we found that, if the cells are incubated with oxygen, they produce hydrogen under the dark. Under 80% argon + 20% oxygen condition, the hydrogen production activity under the dark was about one third of that under the light + argon condition. (2) Also it was necessary so far to incubate the cells under argon atmosphere to produce hydrogen in this system. Argon treatment is very expensive and should be avoided in an actual hydrogen production system. We found that, if the cells are incubated at a high cell density and in a container with minimum headspace, it is not necessary to use argon for the hydrogen production. (3) Calcium ion was found to play an important role in the mechanisms of protection of nitrogenase from external oxygen. This will be a clue to understand the reason why the hydrogen production is so resistant to oxygen in this strain. (4) In this strain, sulfide can be used as electron donor for the hydrogen production. This result shows that waste water can be used for the hydrogen production system using this strain.

  11. Creating biological nanomaterials using synthetic biology

    OpenAIRE

    MaryJoe K Rice; Ruder, Warren C.

    2014-01-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic bi...

  12. Circadian systems biology in Metazoa.

    Science.gov (United States)

    Lin, Li-Ling; Huang, Hsuan-Cheng; Juan, Hsueh-Fen

    2015-11-01

    Systems biology, which can be defined as integrative biology, comprises multistage processes that can be used to understand components of complex biological systems of living organisms and provides hierarchical information to decoding life. Using systems biology approaches such as genomics, transcriptomics and proteomics, it is now possible to delineate more complicated interactions between circadian control systems and diseases. The circadian rhythm is a multiscale phenomenon existing within the body that influences numerous physiological activities such as changes in gene expression, protein turnover, metabolism and human behavior. In this review, we describe the relationships between the circadian control system and its related genes or proteins, and circadian rhythm disorders in systems biology studies. To maintain and modulate circadian oscillation, cells possess elaborative feedback loops composed of circadian core proteins that regulate the expression of other genes through their transcriptional activities. The disruption of these rhythms has been reported to be associated with diseases such as arrhythmia, obesity, insulin resistance, carcinogenesis and disruptions in natural oscillations in the control of cell growth. This review demonstrates that lifestyle is considered as a fundamental factor that modifies circadian rhythm, and the development of dysfunctions and diseases could be regulated by an underlying expression network with multiple circadian-associated signals.

  13. Cell biology perspectives in phage biology.

    Science.gov (United States)

    Ansaldi, Mireille

    2012-01-01

    Cellular biology has long been restricted to large cellular organisms. However, as the resolution of microscopic methods increased, it became possible to study smaller cells, in particular bacterial cells. Bacteriophage biology is one aspect of bacterial cell biology that has recently gained insight from cell biology. Despite their small size, bacteriophages could be successfully labeled and their cycle studied in the host cells. This review aims to put together, although non-extensively, several cell biology studies that recently pushed the elucidation of key mechanisms in phage biology, such as the lysis-lysogeny decision in temperate phages or genome replication and transcription, one step further.

  14. Resisting "Reason"

    DEFF Research Database (Denmark)

    Merrild, Camilla Hoffmann; Andersen, Rikke Sand; Risør, Mette Bech;

    2016-01-01

    Social differences in health and illness are well documented in Denmark. However, little is known about how health practices are manifested in the everyday lives of different social classes. We propose acts of resistance and formation of health subjectivities as helpful concepts to develop our un...

  15. Identification of a locus in Arabidopsis controlling both the expression of rhizobacteria-mediated induced systemic resistance (ISR) and basal resistance against Pseudomonas syringae pv. tomato

    NARCIS (Netherlands)

    Ton, J.; Pieterse, C.M.J.; Loon, L.C. van

    1999-01-01

    Selected nonpathogenic rhizobacteria with biological disease control activity are able to elicit an induced systemic resistance (ISR) response that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). Ten ecotypes of Arabidopsis thaliana were screened for their potential

  16. Biological effects of radiation

    International Nuclear Information System (INIS)

    This fourth chapter presents: cell structure and metabolism; radiation interaction with biological tissues; steps of the production of biological effect of radiation; radiosensitivity of tissues; classification of biological effects; reversibility, transmissivity and influence factors; pre-natal biological effects; biological effects in therapy and syndrome of acute irradiation

  17. 西南地区玉米线形圆斑病生物学特性和品种抗性鉴定%Biological Characters and the Resistance Study of Corn Leaf Spot Caused by Bipolaris zeicola in Southwest China

    Institute of Scientific and Technical Information of China (English)

    张小飞; 崔丽娜; 李晓; 邹成佳; 杨晓蓉

    2013-01-01

    Some biological characters of Bipolaris zeicola and the resistance of fifty varieties were studied. The results showed that the pathogen can grow and develop were between 10℃ and 35℃, and the optimum temperature was between 20℃ and 25℃. For growth of the pathogen, there had no strict pH requirement: the favorable pH was 4 -11 and the optimum pH was 5-7. For germination of conidia, the favorable temperature for conidial germination was between 5℃ and 35℃ and the optimum temperature was 20℃ - 25℃. Effect of light was not obvious on mycelial growth and conidial germination. Different varieties exhibited different disease resistance, the percentage of disease-resistant varieties was 14%, that of moderate resistant varieties was 48%, that of disease susceptible varieties was 38%, the immune and high resistant varieties were not found.%对西南地区普遍发生的玉米线形圆斑病菌生物学特性和50个推广品种对线形圆斑病的抗性进行鉴定.结果表明,该病菌生长温度为10℃~35℃,最适生长温度为20℃~25℃;病原菌对酸碱度的适应范围较广,在pH值4~11都能生长,以pH值为5~7最适;分生孢子在5c℃~35℃均能萌发,最适温度为20℃~25℃;光照对菌丝和孢子萌发无显著影响.玉米品种间对玉米线形圆斑病表现的抗性差异明显,50个品种中表现抗病品种有7个,占14%;中抗品种24个,占48%;感病品种19个,占38%,无免疫品种.

  18. The marked and rapid therapeutic effect of tofacitinib in combination with subcutaneous methotrexate in a rheumatoid arthritis patient with poor prognostic factors who is resistant to standard disease-modifying antirheumatic drugs and biologicals: A clinical case

    Directory of Open Access Journals (Sweden)

    N. V. Demidova

    2016-01-01

    Full Text Available Today, it is generally accepted that it is necessary to achieve clinical remission in rheumatoid arthritis (RA or as minimum a low disease activity. The paper describes a clinical case of a female patient diagnosed with RA who was observed to have inefficiency of standard disease-modifying antirheumatic therapy with methotrexate 25 mg/week, secondary inefficiency of tumor necrosis factor-α inhibitors (adalimumab, and inefficiency/poor tolerance of the interlukin-6 receptor antagonist tocilizumab. This determined the need to use fofacitinib (TOFA, a drug with another mechanism of action. TOFA is the first agent from a new group of immunomodulatory and anti-inflammatory drugs, intracellular kinase inhibitors. Disease remission could be achieved during therapy with TOFA, which enables one to consider this synthetic drug as a therapy option that potentially competes with therapy with biologicals.

  19. Antimicrobial resistance

    DEFF Research Database (Denmark)

    Llor, Carl; Bjerrum, Lars

    2014-01-01

    Antimicrobial resistance is a global public health challenge, which has accelerated by the overuse of antibiotics worldwide. Increased antimicrobial resistance is the cause of severe infections, complications, longer hospital stays and increased mortality. Overprescribing of antibiotics...... is associated with an increased risk of adverse effects, more frequent re-attendance and increased medicalization of self-limiting conditions. Antibiotic overprescribing is a particular problem in primary care, where viruses cause most infections. About 90% of all antibiotic prescriptions are issued by general...... practitioners, and respiratory tract infections are the leading reason for prescribing. Multifaceted interventions to reduce overuse of antibiotics have been found to be effective and better than single initiatives. Interventions should encompass the enforcement of the policy of prohibiting the over...

  20. Evolutionary Biology: Its Value to Society

    Science.gov (United States)

    Carson, Hampton L.

    1972-01-01

    Cites examples of the contribution of basic research in evolutionary biology to the solution of problems facing society (1) by dispelling myths about human origins, the nature of the individual, and the nature of race (2) by providing basic data concerning the effects of overpopulation, the production of improved sources of food, resistance of…

  1. Student Teachers' Approaches to Teaching Biological Evolution

    Science.gov (United States)

    Borgerding, Lisa A.; Klein, Vanessa A.; Ghosh, Rajlakshmi; Eibel, Albert

    2015-01-01

    Evolution is fundamental to biology and scientific literacy, but teaching high school evolution is often difficult. Evolution teachers face several challenges including limited content knowledge, personal conflicts with evolution, expectations of resistance, concerns about students' conflicts with religion, and curricular constraints. Evolution…

  2. 耐糖皮质激素人类弥漫大B细胞淋巴瘤细胞系的建立及其生物学特性观察%Establishment and biological characterization of a human glucocorticoid-resistant cell line of diffuse large B cell lymphoma

    Institute of Scientific and Technical Information of China (English)

    谭微; 陈波斌; 马燕; 许小平; 林果为

    2013-01-01

    Objective To establish a novel glucocorticoid (GC)-resistant human diffuse large B lymphoma(DLBCL) cell line Toledo/dexamethasone (DEX) by the exposure to DEX,and observe the biological characteristics of resistant and parental cell line,investigate the mechanisms of glucocorticoid-resistance.Methods Toledo/DEX was established by the exposure to DEX,the dose of which was increased gradually and intermittently for long periods of time.Toledo,in the logarithmic growth phage,was incubated in the culture medium containing DEX at the concentration of 1×10-8 mol/L at first.The medium without DEX was replaced after for 96 hours until the cell line re-entered the logarithmic growth phase.Repeat the above steps to acquire the ultimate concentration of DEX in the medium as 1.024 ×10-5 mol/L.The biological characteristics of resistant and parental cell lines were evaluated.Results Toledo/DEX was more invasive in the aspects of ultrastructure,tumorigenicity and drug sensitivity.Meanwhile,Toledo/DEX achieved some stable biological characteristics such as morphology,karyotypes and immunophenotype.Furthermore,GC receptor (GR) α and GR β protein expression analysis showed that GR was involved in the mechanism of the GCresistance.Conclusions Toledo/DEX is a drug-resistant cell line with a stable biology backgroud.These results may help shed light on the knowledge of GC-resistance and lay the groundwork for searching new therapeutics to reverse drug-resistance.%目的 采用长期间歇小剂量糖皮质激素(GC)递增诱导法建立耐GC的人类弥漫大B细胞淋巴瘤细胞系Toledo/地塞米松(DEX),并观察耐药和亲本细胞株两者之间的生物学特性差异,探讨其耐药机制.方法 以DEX为诱导剂,将对数期亲本Toledo细胞接种在含DEX起始浓度为1×10-s mol/L的培养液中培养96 h后,改为不含药物的培养液培养,待细胞增殖再次进入对数生长期,提高DEX浓度1倍,直至在含DEX 1.024×10-5 mol/L的浓度中稳定

  3. Biosecurity and Open-Source Biology: The Promise and Peril of Distributed Synthetic Biological Technologies.

    Science.gov (United States)

    Evans, Nicholas G; Selgelid, Michael J

    2015-08-01

    In this article, we raise ethical concerns about the potential misuse of open-source biology (OSB): biological research and development that progresses through an organisational model of radical openness, deskilling, and innovation. We compare this organisational structure to that of the open-source software model, and detail salient ethical implications of this model. We demonstrate that OSB, in virtue of its commitment to openness, may be resistant to governance attempts.

  4. Synthetic biology: insights into biological computation.

    Science.gov (United States)

    Manzoni, Romilde; Urrios, Arturo; Velazquez-Garcia, Silvia; de Nadal, Eulàlia; Posas, Francesc

    2016-04-18

    Organisms have evolved a broad array of complex signaling mechanisms that allow them to survive in a wide range of environmental conditions. They are able to sense external inputs and produce an output response by computing the information. Synthetic biology attempts to rationally engineer biological systems in order to perform desired functions. Our increasing understanding of biological systems guides this rational design, while the huge background in electronics for building circuits defines the methodology. In this context, biocomputation is the branch of synthetic biology aimed at implementing artificial computational devices using engineered biological motifs as building blocks. Biocomputational devices are defined as biological systems that are able to integrate inputs and return outputs following pre-determined rules. Over the last decade the number of available synthetic engineered devices has increased exponentially; simple and complex circuits have been built in bacteria, yeast and mammalian cells. These devices can manage and store information, take decisions based on past and present inputs, and even convert a transient signal into a sustained response. The field is experiencing a fast growth and every day it is easier to implement more complex biological functions. This is mainly due to advances in in vitro DNA synthesis, new genome editing tools, novel molecular cloning techniques, continuously growing part libraries as well as other technological advances. This allows that digital computation can now be engineered and implemented in biological systems. Simple logic gates can be implemented and connected to perform novel desired functions or to better understand and redesign biological processes. Synthetic biological digital circuits could lead to new therapeutic approaches, as well as new and efficient ways to produce complex molecules such as antibiotics, bioplastics or biofuels. Biological computation not only provides possible biomedical and

  5. Synthetic biology: insights into biological computation.

    Science.gov (United States)

    Manzoni, Romilde; Urrios, Arturo; Velazquez-Garcia, Silvia; de Nadal, Eulàlia; Posas, Francesc

    2016-04-18

    Organisms have evolved a broad array of complex signaling mechanisms that allow them to survive in a wide range of environmental conditions. They are able to sense external inputs and produce an output response by computing the information. Synthetic biology attempts to rationally engineer biological systems in order to perform desired functions. Our increasing understanding of biological systems guides this rational design, while the huge background in electronics for building circuits defines the methodology. In this context, biocomputation is the branch of synthetic biology aimed at implementing artificial computational devices using engineered biological motifs as building blocks. Biocomputational devices are defined as biological systems that are able to integrate inputs and return outputs following pre-determined rules. Over the last decade the number of available synthetic engineered devices has increased exponentially; simple and complex circuits have been built in bacteria, yeast and mammalian cells. These devices can manage and store information, take decisions based on past and present inputs, and even convert a transient signal into a sustained response. The field is experiencing a fast growth and every day it is easier to implement more complex biological functions. This is mainly due to advances in in vitro DNA synthesis, new genome editing tools, novel molecular cloning techniques, continuously growing part libraries as well as other technological advances. This allows that digital computation can now be engineered and implemented in biological systems. Simple logic gates can be implemented and connected to perform novel desired functions or to better understand and redesign biological processes. Synthetic biological digital circuits could lead to new therapeutic approaches, as well as new and efficient ways to produce complex molecules such as antibiotics, bioplastics or biofuels. Biological computation not only provides possible biomedical and

  6. Translational environmental biology: cell biology informing conservation.

    Science.gov (United States)

    Traylor-Knowles, Nikki; Palumbi, Stephen R

    2014-05-01

    Typically, findings from cell biology have been beneficial for preventing human disease. However, translational applications from cell biology can also be applied to conservation efforts, such as protecting coral reefs. Recent efforts to understand the cell biological mechanisms maintaining coral health such as innate immunity and acclimatization have prompted new developments in conservation. Similar to biomedicine, we urge that future efforts should focus on better frameworks for biomarker development to protect coral reefs.

  7. Monitoring forest soil properties with electrical resistivity

    OpenAIRE

    Paillet, Y.; Cassagne, N.; Brun, J.J.

    2010-01-01

    Maintenance and monitoring of soil fertility is a key issue for sustainable forest management. Vital ecosystem processes may be affected by management practices which change the physical, chemical and biological properties of the soil. This study is the first in Europe to use electrical resistivity as a non-invasive method to determine forest soil properties rapidly in the field in a monitoring purpose. We explored the correlations between electrical resistivity and forest soil properties on ...

  8. Pictures of Synthetic Biology

    OpenAIRE

    Cserer, Amelie; Seiringer, Alexandra

    2009-01-01

    This article is concerned with the representation of Synthetic Biology in the media and by biotechnology experts. An analysis was made of German-language media articles published between 2004 and 2008, and interviews with biotechnology-experts at the Synthetic Biology conference SB 3.0 in Zurich 2007. The results have been reflected in terms of the definition of Synthetic Biology, applications of Synthetic Biology and the perspectives of opportunities and risks. In the media, Synthetic Biolog...

  9. Computational Systems Chemical Biology

    OpenAIRE

    Oprea, Tudor I.; May, Elebeoba E.; Leitão, Andrei; Tropsha, Alexander

    2011-01-01

    There is a critical need for improving the level of chemistry awareness in systems biology. The data and information related to modulation of genes and proteins by small molecules continue to accumulate at the same time as simulation tools in systems biology and whole body physiologically-based pharmacokinetics (PBPK) continue to evolve. We called this emerging area at the interface between chemical biology and systems biology systems chemical biology, SCB (Oprea et al., 2007).

  10. Resistance welding

    DEFF Research Database (Denmark)

    Bay, Niels; Zhang, Wenqi; Rasmussen, Mogens H.;

    2003-01-01

    Resistance welding comprises not only the well known spot welding process but also more complex projection welding operations, where excessive plastic deformation of the weld point may occur. This enables the production of complex geometries and material combinations, which are often not possible...... to weld by traditional spot welding operations. Such joining processes are, however, not simple to develop due to the large number of parameters involved. Development has traditionally been carried out by large experimental investigations, but the development of a numerical programme system has changed...... this enabling prediction of the welding performance in details. The paper describes the programme in short and gives examples on industrial applications. Finally investigations of causes for failure in a complex industrial joint of two dissimilar metals are carried out combining numerical modelling...

  11. Tamoxifen Resistance: Emerging Molecular Targets.

    Science.gov (United States)

    Rondón-Lagos, Milena; Villegas, Victoria E; Rangel, Nelson; Sánchez, Magda Carolina; Zaphiropoulos, Peter G

    2016-01-01

    17β-Estradiol (E2) plays a pivotal role in the development and progression of breast cancer. As a result, blockade of the E2 signal through either tamoxifen (TAM) or aromatase inhibitors is an important therapeutic strategy to treat or prevent estrogen receptor (ER) positive breast cancer. However, resistance to TAM is the major obstacle in endocrine therapy. This resistance occurs either de novo or is acquired after an initial beneficial response. The underlying mechanisms for TAM resistance are probably multifactorial and remain largely unknown. Considering that breast cancer is a very heterogeneous disease and patients respond differently to treatment, the molecular analysis of TAM's biological activity could provide the necessary framework to understand the complex effects of this drug in target cells. Moreover, this could explain, at least in part, the development of resistance and indicate an optimal therapeutic option. This review highlights the implications of TAM in breast cancer as well as the role of receptors/signal pathways recently suggested to be involved in the development of TAM resistance. G protein-coupled estrogen receptor, Androgen Receptor and Hedgehog signaling pathways are emerging as novel therapeutic targets and prognostic indicators for breast cancer, based on their ability to mediate estrogenic signaling in ERα-positive or -negative breast cancer. PMID:27548161

  12. Allicin: Chemistry and Biological Properties

    Directory of Open Access Journals (Sweden)

    Jan Borlinghaus

    2014-08-01

    Full Text Available Allicin (diallylthiosulfinate is a defence molecule from garlic (Allium sativum L. with a broad range of biological activities. Allicin is produced upon tissue damage from the non-proteinogenic amino acid alliin (S-allylcysteine sulfoxide in a reaction that is catalyzed by the enzyme alliinase. Current understanding of the allicin biosynthetic pathway will be presented in this review. Being a thiosulfinate, allicin is a reactive sulfur species (RSS and undergoes a redox-reaction with thiol groups in glutathione and proteins that is thought to be essential for its biological activity. Allicin is physiologically active in microbial, plant and mammalian cells. In a dose-dependent manner allicin can inhibit the proliferation of both bacteria and fungi or kill cells outright, including antibiotic-resistant strains like methicillin-resistant Staphylococcus aureus (MRSA. Furthermore, in mammalian cell lines, including cancer cells, allicin induces cell-death and inhibits cell proliferation. In plants allicin inhibits seed germination and attenuates root-development. The majority of allicin’s effects are believed to be mediated via redox-dependent mechanisms. In sub-lethal concentrations, allicin has a variety of health-promoting properties, for example cholesterol- and blood pressure-lowering effects that are advantageous for the cardio-vascular system. Clearly, allicin has wide-ranging and interesting applications in medicine and (green agriculture, hence the detailed discussion of its enormous potential in this review. Taken together, allicin is a fascinating biologically active compound whose properties are a direct consequence of the molecule’s chemistry.

  13. Larvicide resistance in Musca domestica (Diptera: Muscidae) populations in Denmark and establishment of resistant laboratory strains.

    Science.gov (United States)

    Kristensen, Michael; Jespersen, Jørgen B

    2003-08-01

    We determined the toxicity of the two IGRs, diflubenzuron and cyromazine, in this survey of resistance in Danish field populations of Musca domestica (L.). We observed resistance toward diflubenzuron and for the first time in Denmark and we found field populations with some resistance to cyromazine. Eleven of the twenty-one field populations had larvae surviving a diagnostic dose of 1.6 times of susceptible LC95 of diflubenzuron and two of these populations had larvae surviving 6.1 times of LC95. Eight of the twenty-one field populations had larvae surviving 2.2 times of susceptible LC95 of cyromazine and one population had larvae surviving 4.4 times of LC95. A fivefold cyromazine resistant strain was established after selection with cyromazine. It was 3-, 5-, and 90-fold resistant to diflubenzuron, triflumuron, and methoprene, respectively. Two diflubenzuron resistant strains (120- and 86-fold, respectively) were established. They showed a high level of resistance to triflumuron (1000- and 200-fold, respectively), and moderate resistance to methoprene (73- and 50-fold, respectively). Both were susceptible to cyromazine. This study shows that by applying the recommendations of previous resistance risk assessments, severe control failures and detrimental development of a high level of resistance have been avoided. The development of resistance has not been completely avoided, but has not developed to a level of biological or economic importance. PMID:14503604

  14. Biology of Blood

    Science.gov (United States)

    ... Mail Facebook TwitterTitle Google+ LinkedIn Home Blood Disorders Biology of Blood Overview of Blood Medical Dictionary Also ... Version. DOCTORS: Click here for the Professional Version Biology of Blood Overview of Blood Components of Blood ...

  15. Advances in Biological Science.

    Science.gov (United States)

    Oppenheimer, Steven B.; And Others

    1988-01-01

    Reviews major developments in areas that are at the cutting edge of biological research. Areas include: human anti-cancer gene, recombinant DNA techniques for the detection of Huntington disease carriers, and marine biology. (CW)

  16. Biology is simple.

    Science.gov (United States)

    Newman, Tim

    2015-12-30

    This paper explores the potential for simplicity to reveal new biological understanding. Borrowing selectively from physics thinking, and contrasting with Crick's reductionist philosophy, the author argues that greater emphasis on simplicity is necessary to advance biology and its applications.

  17. Antibacterial resistance: Current problems and possible solutions

    Directory of Open Access Journals (Sweden)

    Sharma Rashmi

    2005-03-01

    Full Text Available Antimicrobial resistance is a natural biological phenomenon of response of microbes to the selective pressure of an antimicrobial drug. Resistance may be inherent, which explains the phenomenon of opportunistic infection or acquired. Concern about the resistance increased in the late 1990′s and since then, many governmental and agency reports have been published regarding the agricultural use of antibacterials, advising less use of antibacterials, appropriate choice of antibacterials and regimens, prevention of cross-infection and development of new antibacterials. The emergence of multidrug resistant strains of Gram-negative bacteria (Pseudomonas, Klebsiella, Enterobacter, Acinetobacter, Salmonella species and Gram-positve organisms (Staphylococcus, Enterococcus, Streptococcus species is the more worrisome in the present therapeutic scenario. Multidrug - resistant tuberculosis is another serious public health problems. Resistance to some agents can be overcome by modifying the dosage regimens (e.g., using high-dose therapy or inhibiting the resistance mechanism (e.g., beta-lactamase inhibitors, whereas other mechanisms of resistance can only be overcome by using an agent from a different class. It is urgently required to ban the sale of antibiotics without prescription, to use antibiotics more judiciously in hospitals by intensive teaching of the principles of the use of antibiotics and to establish better control measures for nosocomial infections. Thus, it is highly recommended that practicing physicians should become aware of the magnitude of existing problem of antibacterial resistance and help in fighting this deadly threat by rational prescribing.

  18. Engineering scalable biological systems

    OpenAIRE

    Lu, Timothy K.

    2010-01-01

    Synthetic biology is focused on engineering biological organisms to study natural systems and to provide new solutions for pressing medical, industrial, and environmental problems. At the core of engineered organisms are synthetic biological circuits that execute the tasks of sensing inputs, processing logic, and performing output functions. In the last decade, significant progress has been made in developing basic designs for a wide range of biological circuits in bacteria, yeast, and mammal...

  19. Systems interface biology

    OpenAIRE

    Francis J Doyle; Stelling, Jörg

    2006-01-01

    The field of systems biology has attracted the attention of biologists, engineers, mathematicians, physicists, chemists and others in an endeavour to create systems-level understanding of complex biological networks. In particular, systems engineering methods are finding unique opportunities in characterizing the rich behaviour exhibited by biological systems. In the same manner, these new classes of biological problems are motivating novel developments in theoretical systems approaches. Henc...

  20. Biological Races in Humans

    OpenAIRE

    Templeton, Alan R.

    2013-01-01

    Races may exist in humans in a cultural sense, but biological concepts of race are needed to access their reality in a non-species-specific manner and to see if cultural categories correspond to biological categories within humans. Modern biological concepts of race can be implemented objectively with molecular genetic data through hypothesis-testing. Genetic data sets are used to see if biological races exist in humans and in our closest evolutionary relative, the chimpanzee. Using the two m...

  1. Upgrading Undergraduate Biology Education

    Science.gov (United States)

    Musante, Susan

    2011-01-01

    On many campuses throughout the country, undergraduate biology education is in serious need of an upgrade. During the past few decades, the body of biological knowledge has grown exponentially, and as a research endeavor, the practice of biology has evolved. Education research has also made great strides, revealing many new insights into how…

  2. Biology Myth-Killers

    Science.gov (United States)

    Lampert, Evan

    2014-01-01

    "Biology Myth-Killers" is an activity designed to identify and correct common misconceptions for high school and college introductory biology courses. Students identify common myths, which double as biology misconceptions, and use appropriate sources to share the "truth" about the myths. This learner-centered activity is a fun…

  3. Animation of Antimicrobial Resistance

    Science.gov (United States)

    ... Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it ... Veterinary Medicine is cited as the corporate author. Animation Animation of Antimicrobial Resistance (WMV - 19.2MB) 9: ...

  4. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... 08 Animation of Antimicrobial Resistance (text version) Arabic Translation - Animation of Antimicrobial Resistance (WMV - 19.2MB) Chinese Translation - Animation of Antimicrobial Resistance (WMV - 19.2MB) French ...

  5. HIV Resistance Testing

    Science.gov (United States)

    ... 14, 2016 Select a Language: Fact Sheet 126 HIV Resistance Testing WHAT IS RESISTANCE? HOW DOES RESISTANCE ... ARVs. If you miss doses of your medications, HIV will multiply more easily. More mutations will occur. ...

  6. Synthetic biological networks

    International Nuclear Information System (INIS)

    Despite their obvious relationship and overlap, the field of physics is blessed with many insightful laws, while such laws are sadly absent in biology. Here we aim to discuss how the rise of a more recent field known as synthetic biology may allow us to more directly test hypotheses regarding the possible design principles of natural biological networks and systems. In particular, this review focuses on synthetic gene regulatory networks engineered to perform specific functions or exhibit particular dynamic behaviors. Advances in synthetic biology may set the stage to uncover the relationship of potential biological principles to those developed in physics. (review article)

  7. The Biological Control of the Malaria Vector

    Directory of Open Access Journals (Sweden)

    Layla Kamareddine

    2012-09-01

    Full Text Available The call for malaria control, over the last century, marked a new epoch in the history of this disease. Many control strategies targeting either the Plasmodium parasite or the Anopheles vector were shown to be effective. Yet, the emergence of drug resistant parasites and insecticide resistant mosquito strains, along with numerous health, environmental, and ecological side effects of many chemical agents, highlighted the need to develop alternative tools that either complement or substitute conventional malaria control approaches. The use of biological means is considered a fundamental part of the recently launched malaria eradication program and has so far shown promising results, although this approach is still in its infancy. This review presents an overview of the most promising biological control tools for malaria eradication, namely fungi, bacteria, larvivorous fish, parasites, viruses and nematodes.

  8. Progresses in the Mechanism of Resistance to Fusarium Wilt in Cucumber(Cucumis sativus L.)

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xingang; WU Fengzhi; WANG Xuezheng; YUAN Ye

    2008-01-01

    Fusarium wilt caused by Fusarium oxysporum f.sp.cucumerinum (Owen) is one of the most devastating diseases in cucumber production worldwide.Recent progresses in the mechanism of resistance to Fusarium wilt in cucumber were reviewed in this paper,including pathogenic mechanism of Fusarium oxysporum,the resistance mechanism of cucumber,the heredity of resistance,and the location of resistance genes.Following works should be the location and cloning of resistance genes with molecular biologic methods.

  9. Computational systems chemical biology.

    Science.gov (United States)

    Oprea, Tudor I; May, Elebeoba E; Leitão, Andrei; Tropsha, Alexander

    2011-01-01

    There is a critical need for improving the level of chemistry awareness in systems biology. The data and information related to modulation of genes and proteins by small molecules continue to accumulate at the same time as simulation tools in systems biology and whole body physiologically based pharmacokinetics (PBPK) continue to evolve. We called this emerging area at the interface between chemical biology and systems biology systems chemical biology (SCB) (Nat Chem Biol 3: 447-450, 2007).The overarching goal of computational SCB is to develop tools for integrated chemical-biological data acquisition, filtering and processing, by taking into account relevant information related to interactions between proteins and small molecules, possible metabolic transformations of small molecules, as well as associated information related to genes, networks, small molecules, and, where applicable, mutants and variants of those proteins. There is yet an unmet need to develop an integrated in silico pharmacology/systems biology continuum that embeds drug-target-clinical outcome (DTCO) triplets, a capability that is vital to the future of chemical biology, pharmacology, and systems biology. Through the development of the SCB approach, scientists will be able to start addressing, in an integrated simulation environment, questions that make the best use of our ever-growing chemical and biological data repositories at the system-wide level. This chapter reviews some of the major research concepts and describes key components that constitute the emerging area of computational systems chemical biology.

  10. Quantum biological information theory

    CERN Document Server

    Djordjevic, Ivan B

    2016-01-01

    This book is a self-contained, tutorial-based introduction to quantum information theory and quantum biology. It serves as a single-source reference to the topic for researchers in bioengineering, communications engineering, electrical engineering, applied mathematics, biology, computer science, and physics. The book provides all the essential principles of the quantum biological information theory required to describe the quantum information transfer from DNA to proteins, the sources of genetic noise and genetic errors as well as their effects. Integrates quantum information and quantum biology concepts; Assumes only knowledge of basic concepts of vector algebra at undergraduate level; Provides a thorough introduction to basic concepts of quantum information processing, quantum information theory, and quantum biology; Includes in-depth discussion of the quantum biological channel modelling, quantum biological channel capacity calculation, quantum models of aging, quantum models of evolution, quantum models o...

  11. BIOLOGICAL CONTROL OF WEEDS BY MEANS OF PLANT PATHOGENS

    Directory of Open Access Journals (Sweden)

    Marija Ravlić

    2014-06-01

    Full Text Available Biological control is the use of live beneficial organisms and products of their metabolism in the pests control. Plant pathogens can be used for weed control in three different ways: as classical, conservation and augmentative (inoculative and inundated biological control. Inundated biological control involves the use of bioherbicides (mycoherbicides or artificial breeding of pathogens and application in specific stages of crops and weeds. Biological control of weeds can be used where chemical herbicides are not allowed, if resistant weed species are present or in the integrated pest management against weeds with reduced herbicides doses and other non-chemical measures, but it has certain limitations and disadvantages.

  12. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring System ... Note: If you need help accessing information in different file formats, see Instructions for Downloading ...

  13. Study on establishment of paclitaxel resistant osteosarcoma cell line MG63/Taxol and its biological characteristics%人成骨肉瘤MG63紫杉醇耐药细胞系建立及生物学特性研究

    Institute of Scientific and Technical Information of China (English)

    吴文欣; 李维

    2015-01-01

    Objective To establish the paclitaxel(Taxol0 induced osteosarcoma MG63 drug resistance cell subline(MG63/Taxol )and to observe its biological characteristics. Methods Paclitaxel resistant human osteosarcoma cell subline (MG63/Tax-ol) was established by adopting large dose impact combined with small dose maintenance to induce MG63 cell line with Taxol as the inducer. The sensitivity of chemotherapy drugs for the MG63 and MG63/Taxol cell sublines were measured by the colony for-mation assay. The cell morphology change was observed through light microscopy. The proliferation ability of cell lines was mea-sured by growth curve. The cell stages were analyzed by flow cytometry. Results (1)Through 6-month induction,paclitaxel re-sistant osteosarcoma cell subline(MG63/Taxol)was established. (2)The resistant index of MG63/Taxol to Taxol was 10.55. MG63/Taxol also produced the various degrees of cross resistance to cisplatin , methotrexate and 5-Fu. (3)The cell morphology was ob-served through light microscopy. The MG63/Taxol cells were regular arranging, spindle shape and size consistent,MG63/Taxol cell subline was irregular arranging,size inconsistent and morphology showed triangle shape,multiangular shape and multi-nucle-ation.(4)The cell growth cure showed that MG63/Taxol cells grew slowly than the parent cells. (5)The cell cyclical analysis dis-played that the distribution of the G0/G1 stage cells was increased ,while the S stage cells were decreased. Conclusion (1)A pa-clitaxel resistant human osteosarcoma cell subline (MG63/Taxol) established by adopting the large dose impact combined with small dose maintenance(MG63)generates the cross resistance to cisplatin,methotrexate and 5-Fu in different degrees.(2)MG63/Taxol cell subline is significantly different from the parent cell MG63 in the aspects of cell morphology,cell growth curve and cell cycle distribution.%目的:建立紫杉醇(Taxol)诱导的人成骨肉瘤MG63耐药细胞株亚系MG63/Taxol,并观察

  14. Quinolone resistance: much more than predicted

    Directory of Open Access Journals (Sweden)

    Alvaro eHernandez

    2011-02-01

    Full Text Available Since quinolones are synthetic antibiotics, it was predicted that mutations in target genes would be the only mechanism through which resistance could be acquired, because there will not be quinolone resistance genes in nature. Contrary to this prediction, a variety of elements ranging from efflux pumps, target-protecting proteins and even quinolone-modifying enzymes have been shown to contribute to quinolone resistance. The finding of some of these elements in plasmids indicates that quinolone resistance can be transferable. As a result, there has been a developing interest on the reservoirs for quinolone resistance genes and on the potential risks associated with the use of these antibiotics in non-clinical environments. As a matter of fact, plasmid-encoded, quinolone-resistance qnr genes originated in the chromosome of aquatic bacteria, thus the use of quinolones in fish farming might constitute a risk for the emergence of resistance. Failure to predict the development of quinolone resistance reinforces the need of taking into consideration the wide plasticity of biological systems for future predictions. This plasticity allows pathogens to deal with toxic compounds, including those with a synthetic origin as quinolones.

  15. Branching processes in biology

    CERN Document Server

    Kimmel, Marek

    2015-01-01

    This book provides a theoretical background of branching processes and discusses their biological applications. Branching processes are a well-developed and powerful set of tools in the field of applied probability. The range of applications considered includes molecular biology, cellular biology, human evolution and medicine. The branching processes discussed include Galton-Watson, Markov, Bellman-Harris, Multitype, and General Processes. As an aid to understanding specific examples, two introductory chapters, and two glossaries are included that provide background material in mathematics and in biology. The book will be of interest to scientists who work in quantitative modeling of biological systems, particularly probabilists, mathematical biologists, biostatisticians, cell biologists, molecular biologists, and bioinformaticians. The authors are a mathematician and cell biologist who have collaborated for more than a decade in the field of branching processes in biology for this new edition. This second ex...

  16. Foundations of biology

    OpenAIRE

    Sikorav, Jean-Louis; Braslau, Alan; Goldar, Arach

    2014-01-01

    It is often stated that there are no laws in biology, where everything is contingent and could have been otherwise, being solely the result of historical accidents. Furthermore, the customary introduction of fundamental biological entities such as individual organisms, cells, genes, catalysts and motors remains largely descriptive; constructive approaches involving deductive reasoning appear, in comparison, almost absent. As a consequence, both the logical content and principles of biology ne...

  17. Introducing Aquatic Biology

    OpenAIRE

    Kinne, Otto; Browman, Howard I.; Seaman, Matthias

    2007-01-01

    The Inter-Research Science Center (IR) journals Marine Ecology Progress Series (MEPS) and Aquatic Microbial Ecology (AME) have been receiving increasing numbers of high-quality manuscripts that are principally biological, rather than ecological. With regret, we have had to turn these submissions away. Also, leading limnologists have for many years suggested that IR should provide an outlet for top quality articles on freshwater biology and ecology. Aquatic Biology (...

  18. Glycobiology Current Molecular Biology

    OpenAIRE

    Sabire KARAÇALI

    2003-01-01

    Carbohydrate chemistry evolved into carbohydrate biochemistry and gradually into the biology of carbohydrates, or glycobiology, at the end of the last century. Glycobiology is the new research area of modern molecular biology, and it investigates the structure, biosynthesis and biological functions of glycans. The numbers, linkage types (a or b), positions, binding points and functional group differences of monosaccharides create microheterogeneity. Thus, numerous glycoforms with precise stru...

  19. Biological aerosol background characterization

    Science.gov (United States)

    Blatny, Janet; Fountain, Augustus W., III

    2011-05-01

    To provide useful information during military operations, or as part of other security situations, a biological aerosol detector has to respond within seconds or minutes to an attack by virulent biological agents, and with low false alarms. Within this time frame, measuring virulence of a known microorganism is extremely difficult, especially if the microorganism is of unknown antigenic or nucleic acid properties. Measuring "live" characteristics of an organism directly is not generally an option, yet only viable organisms are potentially infectious. Fluorescence based instruments have been designed to optically determine if aerosol particles have viability characteristics. Still, such commercially available biological aerosol detection equipment needs to be improved for their use in military and civil applications. Air has an endogenous population of microorganisms that may interfere with alarm software technologies. To design robust algorithms, a comprehensive knowledge of the airborne biological background content is essential. For this reason, there is a need to study ambient live bacterial populations in as many locations as possible. Doing so will permit collection of data to define diverse biological characteristics that in turn can be used to fine tune alarm algorithms. To avoid false alarms, improving software technologies for biological detectors is a crucial feature requiring considerations of various parameters that can be applied to suppress alarm triggers. This NATO Task Group will aim for developing reference methods for monitoring biological aerosol characteristics to improve alarm algorithms for biological detection. Additionally, they will focus on developing reference standard methodology for monitoring biological aerosol characteristics to reduce false alarm rates.

  20. Antimicrobial Peptides: Versatile Biological Properties

    Directory of Open Access Journals (Sweden)

    Muthuirulan Pushpanathan

    2013-01-01

    Full Text Available Antimicrobial peptides are diverse group of biologically active molecules with multidimensional properties. In recent past, a wide variety of AMPs with diverse structures have been reported from different sources such as plants, animals, mammals, and microorganisms. The presence of unusual amino acids and structural motifs in AMPs confers unique structural properties to the peptide that attribute for their specific mode of action. The ability of these active AMPs to act as multifunctional effector molecules such as signalling molecule, immune modulators, mitogen, antitumor, and contraceptive agent makes it an interesting candidate to study every aspect of their structural and biological properties for prophylactic and therapeutic applications. In addition, easy cloning and recombinant expression of AMPs in heterologous plant host systems provided a pipeline for production of disease resistant transgenic plants. Besides these properties, AMPs were also used as drug delivery vectors to deliver cell impermeable drugs to cell interior. The present review focuses on the diversity and broad spectrum antimicrobial activity of AMPs along with its multidimensional properties that could be exploited for the application of these bioactive peptides as a potential and promising drug candidate in pharmaceutical industries.

  1. Tumour resistance to cisplatin: a modelling approach

    Science.gov (United States)

    Marcu, L.; Bezak, E.; Olver, I.; van Doorn, T.

    2005-01-01

    Although chemotherapy has revolutionized the treatment of haematological tumours, in many common solid tumours the success has been limited. Some of the reasons for the limitations are: the timing of drug delivery, resistance to the drug, repopulation between cycles of chemotherapy and the lack of complete understanding of the pharmacokinetics and pharmacodynamics of a specific agent. Cisplatin is among the most effective cytotoxic agents used in head and neck cancer treatments. When modelling cisplatin as a single agent, the properties of cisplatin only have to be taken into account, reducing the number of assumptions that are considered in the generalized chemotherapy models. The aim of the present paper is to model the biological effect of cisplatin and to simulate the consequence of cisplatin resistance on tumour control. The 'treated' tumour is a squamous cell carcinoma of the head and neck, previously grown by computer-based Monte Carlo techniques. The model maintained the biological constitution of a tumour through the generation of stem cells, proliferating cells and non-proliferating cells. Cell kinetic parameters (mean cell cycle time, cell loss factor, thymidine labelling index) were also consistent with the literature. A sensitivity study on the contribution of various mechanisms leading to drug resistance is undertaken. To quantify the extent of drug resistance, the cisplatin resistance factor (CRF) is defined as the ratio between the number of surviving cells of the resistant population and the number of surviving cells of the sensitive population, determined after the same treatment time. It is shown that there is a supra-linear dependence of CRF on the percentage of cisplatin-DNA adducts formed, and a sigmoid-like dependence between CRF and the percentage of cells killed in resistant tumours. Drug resistance is shown to be a cumulative process which eventually can overcome tumour regression leading to treatment failure.

  2. Tumour resistance to cisplatin: a modelling approach

    International Nuclear Information System (INIS)

    Although chemotherapy has revolutionized the treatment of haematological tumours, in many common solid tumours the success has been limited. Some of the reasons for the limitations are: the timing of drug delivery, resistance to the drug, repopulation between cycles of chemotherapy and the lack of complete understanding of the pharmacokinetics and pharmacodynamics of a specific agent. Cisplatin is among the most effective cytotoxic agents used in head and neck cancer treatments. When modelling cisplatin as a single agent, the properties of cisplatin only have to be taken into account, reducing the number of assumptions that are considered in the generalized chemotherapy models. The aim of the present paper is to model the biological effect of cisplatin and to simulate the consequence of cisplatin resistance on tumour control. The 'treated' tumour is a squamous cell carcinoma of the head and neck, previously grown by computer-based Monte Carlo techniques. The model maintained the biological constitution of a tumour through the generation of stem cells, proliferating cells and non-proliferating cells. Cell kinetic parameters (mean cell cycle time, cell loss factor, thymidine labelling index) were also consistent with the literature. A sensitivity study on the contribution of various mechanisms leading to drug resistance is undertaken. To quantify the extent of drug resistance, the cisplatin resistance factor (CRF) is defined as the ratio between the number of surviving cells of the resistant population and the number of surviving cells of the sensitive population, determined after the same treatment time. It is shown that there is a supra-linear dependence of CRF on the percentage of cisplatin-DNA adducts formed, and a sigmoid-like dependence between CRF and the percentage of cells killed in resistant tumours. Drug resistance is shown to be a cumulative process which eventually can overcome tumour regression leading to treatment failure

  3. Linezolid Resistance in Staphylococcus aureus: Gene Dosage Effect, Stability, Fitness Costs, and Cross-Resistances▿

    OpenAIRE

    Besier, Silke; Ludwig, Albrecht; Zander, Johannes; Brade, Volker; Wichelhaus, Thomas A.

    2008-01-01

    Linezolid resistance in Staphylococcus aureus is typically associated with mutations in the 23S rRNA gene. Here we show that the accumulation of a single point mutation, G2576T, in the different copies of this gene causes stepwise increases in resistance, impairment of the biological fitness, and cross-resistance to quinupristin-dalfopristin and chloramphenicol.

  4. Antibiotic resistance: from Darwin to Lederberg to Keynes.

    Science.gov (United States)

    Amábile-Cuevas, Carlos F

    2013-04-01

    The emergence and spread of antibiotic-resistant bacteria reflects both, a gradual, completely Darwinian evolution, which mostly yields slight decreases in antibiotic susceptibility, along with phenotypes that are not precisely characterized as "resistance"; and sudden changes, from full susceptibility to full resistance, which are driven by a vast array of horizontal gene transfer mechanisms. Antibiotics select for more than just antibiotic resistance (i.e., increased virulence and enhanced gene exchange abilities); and many non-antibiotic agents or conditions select for or maintain antibiotic resistance traits as a result of a complex network of underlying and often overlapping mechanisms. Thus, the development of new antibiotics and thoughtful, integrated anti-infective strategies is needed to address the immediate and long-term threat of antibiotic resistance. Since the biology of resistance is complex, these new drugs and strategies will not come from free-market forces, or from "incentives" for pharmaceutical companies.

  5. Resistance patterns, prevalence, and predictors of fluoroquinolones resistance in multidrug resistant tuberculosis patients

    OpenAIRE

    Nafees Ahmad; Arshad Javaid; Syed Azhar Syed Sulaiman; Long Chiau Ming; Izaz Ahmad; Amer Hayat Khan

    2016-01-01

    Abstract Background Fluoroquinolones are the backbone of multidrug resistant tuberculosis treatment regimens. Despite the high burden of multidrug resistant tuberculosis in the country, little is known about drug resistance patterns, prevalence, and predictors of fluoroquinolones resistance among multidrug resistant tuberculosis patients from Pakistan. Objective To evaluate drug resistance patterns, prevalence, and predictors of fluoroquinolones resistance in multidrug resistant tuberculosi...

  6. Integrated Biological Control

    International Nuclear Information System (INIS)

    Biological control is any activity taken to prevent, limit, clean up, or remediate potential environmental, health and safety, or workplace quality impacts from plants, animals, or microorganisms. At Hanford the principal emphasis of biological control is to prevent the transport of radioactive contamination by biological vectors (plants, animals, or microorganisms), and where necessary, control and clean up resulting contamination. Other aspects of biological control at Hanford include industrial weed control (e.g.; tumbleweeds), noxious weed control (invasive, non-native plant species), and pest control (undesirable animals such as rodents and stinging insects; and microorganisms such as molds that adversely affect the quality of the workplace environment). Biological control activities may be either preventive (apriori) or in response to existing contamination spread (aposteriori). Surveillance activities, including ground, vegetation, flying insect, and other surveys, and apriori control actions, such as herbicide spraying and placing biological barriers, are important in preventing radioactive contamination spread. If surveillance discovers that biological vectors have spread radioactive contamination, aposteriori control measures, such as fixing contamination, followed by cleanup and removal of the contamination to an approved disposal location are typical response functions. In some cases remediation following the contamination cleanup and removal is necessary. Biological control activities for industrial weeds, noxious weeds and pests have similar modes of prevention and response

  7. Biological pretreatment sewages water

    OpenAIRE

    Veselý, Václav

    2009-01-01

    Bachelor's thesis deals with waste water purification at the stage of pre-inflow of water into the biological waste water treatment plants. It is divided into two parts, a theoretical and calculation. The theoretical part deals about sewage water and the method of biological treatment. Design proposal is part of the activation tank for quantity EO.

  8. Experimenting with Mathematical Biology

    Science.gov (United States)

    Sanft, Rebecca; Walter, Anne

    2016-01-01

    St. Olaf College recently added a Mathematical Biology concentration to its curriculum. The core course, Mathematics of Biology, was redesigned to include a wet laboratory. The lab classes required students to collect data and implement the essential modeling techniques of formulation, implementation, validation, and analysis. The four labs…

  9. Biological Macromolecule Crystallization Database

    Science.gov (United States)

    SRD 21 Biological Macromolecule Crystallization Database (Web, free access)   The Biological Macromolecule Crystallization Database and NASA Archive for Protein Crystal Growth Data (BMCD) contains the conditions reported for the crystallization of proteins and nucleic acids used in X-ray structure determinations and archives the results of microgravity macromolecule crystallization studies.

  10. Bioinformatics and School Biology

    Science.gov (United States)

    Dalpech, Roger

    2006-01-01

    The rapidly changing field of bioinformatics is fuelling the need for suitably trained personnel with skills in relevant biological "sub-disciplines" such as proteomics, transcriptomics and metabolomics, etc. But because of the complexity--and sheer weight of data--associated with these new areas of biology, many school teachers feel…

  11. Optics of Biological Particles

    CERN Document Server

    Hoekstra, Alfons; Videen, Gorden

    2007-01-01

    This book covers the optics of single biological particles, both theory and experiment, with emphasis on Elastic Light Scattering and Fluorescence. It deals with the optics of bacteria (bio-aerosols), marine particles (selected phytoplankton communities) and red and white blood cells. Moreover, there are dedicated chapters on a general theory for scattering by a cell, and modelling and simulation of scattering by inhomogeneous biological cells. Finally, one chapter is dedicated to astro-biological signatures, discussing the possibilities for detecting non-terrestrial biological material. The volume has up-to-date discussions on new experimental and numerical techniques, and many examples of applications of these techniques in real-life systems, as used to detect and characterize e.g. biological warfare agents or human blood cells.

  12. Frontiers in mathematical biology

    CERN Document Server

    1994-01-01

    Volume 100, which is the final volume of the LNBM series serves to commemorate the acievements in two decades of this influential collection of books in mathematical biology. The contributions, by the leading mathematical biologists, survey the state of the art in the subject, and offer speculative, philosophical and critical analyses of the key issues confronting the field. The papers address fundamental issues in cell and molecular biology, organismal biology, evolutionary biology, population ecology, community and ecosystem ecology, and applied biology, plus the explicit and implicit mathematical challenges. Cross-cuttting issues involve the problem of variation among units in nonlinear systems, and the related problems of the interactions among phenomena across scales of space, time and organizational complexity.

  13. Molecular mechanisms for tumour resistance to chemotherapy.

    Science.gov (United States)

    Pan, Shu-Ting; Li, Zhi-Ling; He, Zhi-Xu; Qiu, Jia-Xuan; Zhou, Shu-Feng

    2016-08-01

    Chemotherapy is one of the prevailing methods used to treat malignant tumours, but the outcome and prognosis of tumour patients are not optimistic. Cancer cells gradually generate resistance to almost all chemotherapeutic drugs via a variety of distinct mechanisms and pathways. Chemotherapeutic resistance, either intrinsic or acquired, is caused and sustained by reduced drug accumulation and increased drug export, alterations in drug targets and signalling transduction molecules, increased repair of drug-induced DNA damage, and evasion of apoptosis. In order to better understand the mechanisms of chemoresistance, this review highlights our current knowledge of the role of altered drug metabolism and transport and deregulation of apoptosis and autophagy in the development of tumour chemoresistance. Reduced intracellular activation of prodrugs (e.g. thiotepa and tegafur) or enhanced drug inactivation by Phase I and II enzymes contributes to the development of chemoresistance. Both primary and acquired resistance can be caused by alterations in the transport of anticancer drugs which is mediated by a variety of drug transporters such as P-glycoprotein (P-gp), multidrug resistance associated proteins, and breast cancer resistance protein. Presently there is a line of evidence indicating that deregulation of programmed cell death including apoptosis and autophagy is also an important mechanism for tumour resistance to anticancer drugs. Reversal of chemoresistance is likely via pharmacological and biological approaches. Further studies are warranted to grasp the full picture of how each type of cancer cells develop resistance to anticancer drugs and to identify novel strategies to overcome it.

  14. Molecular mechanisms for tumour resistance to chemotherapy.

    Science.gov (United States)

    Pan, Shu-Ting; Li, Zhi-Ling; He, Zhi-Xu; Qiu, Jia-Xuan; Zhou, Shu-Feng

    2016-08-01

    Chemotherapy is one of the prevailing methods used to treat malignant tumours, but the outcome and prognosis of tumour patients are not optimistic. Cancer cells gradually generate resistance to almost all chemotherapeutic drugs via a variety of distinct mechanisms and pathways. Chemotherapeutic resistance, either intrinsic or acquired, is caused and sustained by reduced drug accumulation and increased drug export, alterations in drug targets and signalling transduction molecules, increased repair of drug-induced DNA damage, and evasion of apoptosis. In order to better understand the mechanisms of chemoresistance, this review highlights our current knowledge of the role of altered drug metabolism and transport and deregulation of apoptosis and autophagy in the development of tumour chemoresistance. Reduced intracellular activation of prodrugs (e.g. thiotepa and tegafur) or enhanced drug inactivation by Phase I and II enzymes contributes to the development of chemoresistance. Both primary and acquired resistance can be caused by alterations in the transport of anticancer drugs which is mediated by a variety of drug transporters such as P-glycoprotein (P-gp), multidrug resistance associated proteins, and breast cancer resistance protein. Presently there is a line of evidence indicating that deregulation of programmed cell death including apoptosis and autophagy is also an important mechanism for tumour resistance to anticancer drugs. Reversal of chemoresistance is likely via pharmacological and biological approaches. Further studies are warranted to grasp the full picture of how each type of cancer cells develop resistance to anticancer drugs and to identify novel strategies to overcome it. PMID:27097837

  15. Tumor microenvironment and cancer therapy resistance.

    Science.gov (United States)

    Sun, Yu

    2016-09-28

    Innate resistance to various therapeutic interventions is a hallmark of cancer. In recent years, however, acquired resistance has emerged as a daunting challenge to anticancer treatments including chemotherapy, radiation and targeted therapy, which abolishes the efficacy of otherwise successful regimens. Cancer cells gain resistance through a variety of mechanisms in both primary and metastatic sites, involving cell intrinsic and extrinsic factors, but the latter often remains overlooked. Mounting evidence suggests critical roles played by the tumor microenvironment (TME) in multiple aspects of cancer progression particularly therapeutic resistance. The TME decreases drug penetration, confers proliferative and antiapoptotic advantages to surviving cells, facilitates resistance without causing genetic mutations and epigenetic changes, collectively modifying disease modality and distorting clinical indices. Recent studies have set the baseline for future investigation on the intricate relationship between cancer resistance and the TME in pathological backgrounds. This review provides an updated outline of research advances in TME biology and highlights the prospect of targeting the TME as an essential strategy to overcome cancer resistance and improve therapeutic outcomes through precise intervention. In the long run, continued inputs into translational medicine remain highly desired to achieve durable responses in the current era of personalized clinical oncology. PMID:26272180

  16. Biologically-Inspired Electronics with Memory Circuit Elements

    OpenAIRE

    Di Ventra, M.; Pershin, Y. V.

    2011-01-01

    Several abilities of biological systems, such as adaptation to natural environment, or of animals to learn patterns when appropriately trained, are features that are extremely useful, if emulated by electronic circuits, in applications ranging from robotics to solution of complex optimization problems, traffic control, etc. In this chapter, we discuss several examples of biologically-inspired circuits that take advantage of memory circuit elements, namely, electronic elements whose resistive,...

  17. Non-natural Nucleic Acids for Synthetic Biology

    OpenAIRE

    Appella, Daniel H.

    2009-01-01

    Genetic manipulation is an important facet of synthetic biology but can be complicated by undesired nuclease degradation. Incorporating non-natural nucleic acids into a gene could convey resistance to nucleases and promote expression. The compatibility of non-natural nucleosides with polymerases is reviewed with a focus on results from the past two years. Details are provided about how the different systems could be useful in synthetic biology.

  18. 等渗透势干旱、盐、碱胁迫下5个枣品种及酸枣的生物学响应与抗逆性%Biological responses and resistances of five cultivars of Chinese jujube and sour date under iso-osmotic drought, salt and alkaline stresses

    Institute of Scientific and Technical Information of China (English)

    徐呈祥

    2012-01-01

    试验研究等渗透势干旱、盐、碱胁迫下枣和酸枣的生物学响应,鉴评它们对这3种主要的非生物胁迫的抗性差异.以2年生金丝小枣等5个枣品种及砧木—酸枣苗为试材,在-0.30 MPa、-1.15 MPa 2种渗透势下,设计干旱胁迫(用PEG-6 000模拟)、盐(NaCl)胁迫、碱(NaHCO3)胁迫3种逆境,以浇灌1/2Hoagland溶液、不加PEG-6000或NaCl或NaHCO3的处理为对照.生物量较生长量更能准确反映枣和酸枣对干旱、盐、碱胁迫的响应,但其中各个指标的响应存在显著差异:在植株生长量诸指标中,株高特别是冠幅的差异性很小,对胁迫种类及强度敏感度低,而枣头枝长度和基部直径对胁迫种类及强度的敏感度明显为高,是以生长量反映对胁迫响应的合适指标;在生物量诸指标中,植株叶生物量、脱落性枝生物量的响应最敏感,其次是全株生物量,茎生物量、根生物量的响应最不敏感, (叶+脱落性枝)生物量/全株生物量的响应与全株生物量的响应相似.以(叶+脱落性枝)生物量、全株生物量及(叶+脱落性枝)生物量/全株生物量3项关键指标综合评价,参试的5个枣品种及酸枣对前述逆境的抗性差异显著.其中:耐旱性最强的是大瓜枣和梨枣,耐盐性最强的是大瓜枣,耐碱性最强的是酸枣和大瓜枣.同时,5个枣品种及酸枣各自对3种逆境的响应也有明显差异:大瓜枣是一个对3种非生物逆境抗性都很优良的枣品种;冬枣既不耐干旱,也不耐盐碱,但相对而言,其耐盐性>抗旱性>耐碱性.枣属植物对干旱、盐、碱胁迫的抗性实际上存在很大差异.枣树引种栽培应重视品种的生理生态特性.枣优良新品种培育应关注亲本品种本身对主要逆境的抗性.%The biological responses of five Chineses jujube cultivars and sour date mainly grown in East China to iso-osmotic drought, salt and alkaline stresses were investigated and the resistant

  19. [Drug resistant epilepsy. Clinical and neurobiological concepts].

    Science.gov (United States)

    Espinosa-Jovel, Camilo A; Sobrino-Mejía, Fidel E

    2015-08-16

    Drug-resistant epilepsy, is a condition defined by the International League Against Epilepsy as persistent seizures despite having used at least two appropriate and adequate antiepileptic drug treatments. Approximately 20-30% of patients with epilepsy are going to be resistant to antiepileptic drugs, with different patterns of clinical presentation, which are related to the biological basis of this disease (de novo resistance, relapsing-remitting and progressive). Drug resistant epilepsy, impacts negatively the quality of life and significantly increases the risk of premature death. From the neurobiological point of view, this medical condition is the result of the interaction of multiple variables related to the underlying disease, drug interactions and proper genetic aspects of each patient. Thanks to advances in pharmacogenetics and molecular biology research, currently some hypotheses may explain the cause of this condition and promote the study of new therapeutic options. Currently, overexpression of membrane transporters such as P-glycoprotein, appears to be one of the most important mechanisms in the development of drug resistant epilepsy. The objective of this review is to deepen the general aspects of this clinical condition, addressing the definition, epidemiology, differential diagnosis and the pathophysiological bases.

  20. A Hypothesis on Biological Protection from Space Radiation Through the Use of Therapeutic Gases

    Science.gov (United States)

    Schoenfeld, Michael

    2011-01-01

    This slide presentation proposes a hypothesis to use therapeutic gases in space to enhance the biological protection for astronauts from space radiation. The fundamental role in how radiation causes biological damage appears to be radiolysis, the dissociation of water by radiation. A chain of events appears to cause molecular and biological transformations that ultimately manifest into medical diseases. The hypothesis of this work is that applying medical gases may increase resistance to radiation, by possessing the chemical properties that effectively improve the radical scavenging and enhance bond repair and to induce biological processes which enhance and support natural resistance and repair mechanisms.

  1. Managing biological diversity

    Science.gov (United States)

    Samson, Fred B.; Knopf, Fritz L.

    1993-01-01

    Biological diversity is the variety of life and accompanying ecological processes (Off. Technol. Assess. 1987, Wilcove and Samson 1987, Keystone 1991). Conservation of biological diversity is a major environmental issue (Wilson 1988, Counc. Environ. Quality 1991). The health and future of the earth's ecological systems (Lubchenco et al. 1991), global climate change (Botkin 1990), and an ever-increasing rate in loss of species, communities, and ecological systems (Myers 1990) are among issues drawing biological diversity to the mainstream of conservation worldwide (Int. Union Conserv. Nat. and Nat. Resour. [IUCN] et al. 1991). The legal mandate for conserving biological diversity is now in place (Carlson 1988, Doremus 1991). More than 19 federal laws govern the use of biological resources in the United States (Rein 1991). The proposed National Biological Diversity Conservation and Environmental Research Act (H.R. 585 and S.58) notes the need for a national biological diversity policy, would create a national center for biological diversity research, and recommends a federal interagency strategy for ecosystem conservation. There are, however, hard choices ahead for the conservation of biological diversity, and biologists are grappling with how to set priorities in research and management (Roberts 1988). We sense disillusion among field biologists and managers relative to how to operationally approach the seemingly overwhelming charge of conserving biological diversity. Biologists also need to respond to critics like Hunt (1991) who suggest a tree farm has more biological diversity than an equal area of old-growth forest. At present, science has played only a minor role in the conservation of biological diversity (Weston 1992) with no unified approach available to evaluate strategies and programs that address the quality and quantity of biological diversity (Murphy 1990, Erwin 1992). Although actions to conserve biological diversity need to be clearly defined by

  2. Biology and Mathematics

    Directory of Open Access Journals (Sweden)

    Bascompte, Jordi

    2007-06-01

    Full Text Available Biology has become the new “physics” of mathematics, one of the areas of greatest mathematical applications. In turn, mathematics has provided powerful tools and metaphors to approach the astonishing complexity of biological systems. This has allowed the development of sound theoretical frameworks. Here, I summarize some of the most significant contributions of mathematics to biology, ranging from population genetics, to developmental biology, and to networks of species interactions.La biología se ha convertido en la nueva “física” de las matemáticas, una de las áreas con mayores aplicaciones. Las matemáticas, por su parte, han proporcionado herramientas y metáforas muy poderosas para abordar la increíble complejidad de los sistemas biológicos. Esto ha permitido la génesis de marcos conceptuales sólidos. En este artículo resumo algunas de las aplicaciones más exitosas de las matemáticas a la biología que van desde la genética de poblaciones a la biología del desarrollo y las redes de interacciones ecológicas.

  3. Biological and Chemical Security

    Energy Technology Data Exchange (ETDEWEB)

    Fitch, P J

    2002-12-19

    The LLNL Chemical & Biological National Security Program (CBNP) provides science, technology and integrated systems for chemical and biological security. Our approach is to develop and field advanced strategies that dramatically improve the nation's capabilities to prevent, prepare for, detect, and respond to terrorist use of chemical or biological weapons. Recent events show the importance of civilian defense against terrorism. The 1995 nerve gas attack in Tokyo's subway served to catalyze and focus the early LLNL program on civilian counter terrorism. In the same year, LLNL began CBNP using Laboratory-Directed R&D investments and a focus on biodetection. The Nunn-Lugar-Domenici Defense Against Weapons of Mass Destruction Act, passed in 1996, initiated a number of U.S. nonproliferation and counter-terrorism programs including the DOE (now NNSA) Chemical and Biological Nonproliferation Program (also known as CBNP). In 2002, the Department of Homeland Security was formed. The NNSA CBNP and many of the LLNL CBNP activities are being transferred as the new Department becomes operational. LLNL has a long history in national security including nonproliferation of weapons of mass destruction. In biology, LLNL had a key role in starting and implementing the Human Genome Project and, more recently, the Microbial Genome Program. LLNL has over 1,000 scientists and engineers with relevant expertise in biology, chemistry, decontamination, instrumentation, microtechnologies, atmospheric modeling, and field experimentation. Over 150 LLNL scientists and engineers work full time on chemical and biological national security projects.

  4. Beyond the Biology: A Systematic Investigation of Noncontent Instructor Talk in an Introductory Biology Course

    OpenAIRE

    Seidel, Shannon B.; Reggi, Amanda L.; Schinske, Jeffrey N.; Burrus, Laura W.; Tanner, Kimberly D.

    2015-01-01

    Instructors create classroom environments that have the potential to impact learning by affecting student motivation, resistance, and self-efficacy. However, despite the critical importance of the learning environment in increasing conceptual understanding, little research has investigated what instructors say and do to create learning environments in college biology classrooms. We systematically investigated the language used by instructors that does not directly relate to course content and...

  5. Neutron in biology

    Energy Technology Data Exchange (ETDEWEB)

    Niimura, Nobuo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-11-01

    Neutron in biology can provide an experimental method of directly locating relationship of proteins and DNA. However, there are relatively few experimental study of such objects since it takes a lot of time to collect a sufficient number of Bragg reflections and inelastic spectra due to the low flux of neutron illuminating the sample. Since a next generation neutron source of JAERI will be 5MW spallation neutron source and its effective neutron flux will be 10{sup 2} to 10{sup 3} times higher than the one of JRR-3M, neutron in biology will open a completely new world for structural biology. (author)

  6. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring System About NARMS Bacteria (NARMS) NARMS at Work Reports ... Emergency Preparedness International Programs News & Events Training & Continuing Education Inspections & Compliance Federal, State & Local Officials Consumers Health ...

  7. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... how antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the development of resistant strains of bacteria, complicating clinician's efforts to select the appropriate antimicrobial ...

  8. HIV Genotypic Resistance Testing

    Science.gov (United States)

    ... of the disease progression and to minimize viral replication and mutation. However, a person may be initially infected with a drug-resistant HIV strain or drug resistance may develop during treatment, ...

  9. Mobile antibiotic resistance - the spread of genes determining the resistance of bacteria through food products.

    Science.gov (United States)

    Godziszewska, Jolanta; Guzek, Dominika; Głąbski, Krzysztof; Wierzbicka, Agnieszka

    2016-01-01

    In recent years, more and more antibiotics have become ineffective in the treatment of bacterial nfections. The acquisition of antibiotic resistance by bacteria is associated with circulation of genes in the environment. Determinants of antibiotic resistance may be transferred to pathogenic bacteria. It has been shown that conjugation is one of the key mechanisms responsible for spread of antibiotic resistance genes, which is highly efficient and allows the barrier to restrictions and modifications to be avoided. Some conjugative modules enable the transfer of plasmids even between phylogenetically distant bacterial species. Many scientific reports indicate that food is one of the main reservoirs of these genes. Antibiotic resistance genes have been identified in meat products, milk, fruits and vegetables. The reason for such a wide spread of antibiotic resistance genes is the overuse of antibiotics by breeders of plants and animals, as well as by horizontal gene transfer. It was shown, that resistance determinants located on mobile genetic elements, which are isolated from food products, can easily be transferred to another niche. The antibiotic resistance genes have been in the environment for 30 000 years. Their removal from food products is not possible, but the risks associated with the emergence of multiresistant pathogenic strains are very large. The only option is to control the emergence, selection and spread of these genes. Therefore measures are sought to prevent horizontal transfer of genes. Promising concepts involve the combination of developmental biology, evolution and ecology in the fight against the spread of antibiotic resistance. PMID:27383577

  10. A Molecular Biology Database Digest

    OpenAIRE

    Bry, François; Kröger, Peer

    2000-01-01

    Computational Biology or Bioinformatics has been defined as the application of mathematical and Computer Science methods to solving problems in Molecular Biology that require large scale data, computation, and analysis [18]. As expected, Molecular Biology databases play an essential role in Computational Biology research and development. This paper introduces into current Molecular Biology databases, stressing data modeling, data acquisition, data retrieval, and the integration...

  11. Pneumococcal resistance to antibiotics.

    OpenAIRE

    Klugman, K P

    1990-01-01

    The geographic distribution of pneumococci resistant to one or more of the antibiotics penicillin, erythromycin, trimethoprim-sulfamethoxazole, and tetracycline appears to be expanding, and there exist foci of resistance to chloramphenicol and rifampin. Multiply resistant pneumococci are being encountered more commonly and are more often community acquired. Factors associated with infection caused by resistant pneumococci include young age, duration of hospitalization, infection with a pneumo...

  12. Applications of dynamical systems in biology and medicine

    CERN Document Server

    Radunskaya, Ami

    2015-01-01

    This volume highlights problems from a range of biological and medical applications that can be interpreted as questions about system behavior or control.  Topics include drug resistance in cancer and malaria, biological fluid dynamics, auto-regulation in the kidney, anti-coagulation therapy, evolutionary diversification and photo-transduction.  Mathematical techniques used to describe and investigate these biological and medical problems include ordinary, partial and stochastic differentiation equations, hybrid discrete-continuous approaches, as well as 2 and 3D numerical simulation. .

  13. Large Pelagics Biological Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Large Pelagics Biological Survey (LPBS) collects additional length and weight information and body parts such as otoliths, caudal vertebrae, dorsal spines, and...

  14. Hammond Bay Biological Station

    Data.gov (United States)

    Federal Laboratory Consortium — Hammond Bay Biological Station (HBBS), located near Millersburg, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). HBBS was established by...

  15. The Biology of Behaviour.

    Science.gov (United States)

    Broom, D. M.

    1981-01-01

    Discusses topics to aid in understanding animal behavior, including the value of the biological approach to psychology, functional systems, optimality and fitness, universality of environmental effects on behavior, and evolution of social behavior. (DS)

  16. Laboratory of Biological Modeling

    Data.gov (United States)

    Federal Laboratory Consortium — The Laboratory of Biological Modeling is defined by both its methodologies and its areas of application. We use mathematical modeling in many forms and apply it to...

  17. Insecticides and Biological Control

    Science.gov (United States)

    Furness, G. O.

    1972-01-01

    Use of insecticides has been questioned due to their harmful effects on edible items. Biological control of insects along with other effective practices for checking spread of parasites on crops are discussed. (PS)

  18. Chemistry and biology data

    Data.gov (United States)

    U.S. Environmental Protection Agency — Chemical monitoring data and biological data from field collected samples. This dataset is associated with the following publication: Biales , A., D. Denton , D....

  19. Fishery Biology Database (AGDBS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Basic biological data are the foundation on which all assessments of fisheries resources are built. These include parameters such as the size and age composition of...

  20. Mammalian cell biology

    International Nuclear Information System (INIS)

    This section contains summaries of research on mechanisms of lethality and radioinduced changes in mammalian cell properties, new cell systems for the study of the biology of mutation and neoplastic transformation, and comparative properties of ionizing radiations

  1. Enhanced Biological Sampling Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a database of a variety of biological, reproductive, and energetic data collected from fish on the continental shelf in the northwest Atlantic Ocean....

  2. Precision Measurement in Biology

    Science.gov (United States)

    Quake, Stephen

    Is biology a quantitative science like physics? I will discuss the role of precision measurement in both physics and biology, and argue that in fact both fields can be tied together by the use and consequences of precision measurement. The elementary quanta of biology are twofold: the macromolecule and the cell. Cells are the fundamental unit of life, and macromolecules are the fundamental elements of the cell. I will describe how precision measurements have been used to explore the basic properties of these quanta, and more generally how the quest for higher precision almost inevitably leads to the development of new technologies, which in turn catalyze further scientific discovery. In the 21st century, there are no remaining experimental barriers to biology becoming a truly quantitative and mathematical science.

  3. Mechanical Biological Treatment

    DEFF Research Database (Denmark)

    Bilitewski, B-; Oros, Christiane; Christensen, Thomas Højlund

    2011-01-01

    The basic processes and technologies of composting and anaerobic digestion, as described in the previous chapters, are usually used for specific or source-separated organic waste flows. However, in the 1990s mechanical biological waste treatment technologies (MBT) were developed for unsorted...... or residual waste (after some recyclables removed at the source). The concept was originally to reduce the amount of waste going to landfill, but MBT technologies are today also seen as plants recovering fuel as well as material fractions. As the name suggests the technology combines mechanical treatment...... technologies (screens, sieves, magnets, etc.) with biological technologies (composting, anaerobic digestion). Two main technologies are available: Mechanical biological pretreatment (MBP), which first removes an RDF fraction and then biologically treats the remaining waste before most of it is landfilled...

  4. [Systems biology of cancer].

    Science.gov (United States)

    Barillot, Emmanuel; Calzone, Laurence; Zinovyev, Andrei

    2009-01-01

    Cancer Systems Biology is now accepted and recognized as a promising field both in biological and clinical research. It relies on a rigorous formalization of regulation networks into precise and unambiguous languages. It provides both detailed and modular views of the complex biological system of interest (which in cancer research is typically an interaction network governing essential cellular events such as proliferation, differentiation, cell death...) in order to facilitate the interpretation of molecular profiles of tumors. The translation of these networks into mathematical models allows prediction of the evolution of the system in time and under certain perturbations. As a result, it can not only propose specific target points for pharmaceutical purposes, but also anticipate the evolution of tumors as well as their classifications. These characteristics emphasize the important role of Systems Biology of Cancer in the future of biomedical research.

  5. Thermodynamics of Biological Processes

    Science.gov (United States)

    Garcia, Hernan G.; Kondev, Jane; Orme, Nigel; Theriot, Julie A.; Phillips, Rob

    2012-01-01

    There is a long and rich tradition of using ideas from both equilibrium thermodynamics and its microscopic partner theory of equilibrium statistical mechanics. In this chapter, we provide some background on the origins of the seemingly unreasonable effectiveness of ideas from both thermodynamics and statistical mechanics in biology. After making a description of these foundational issues, we turn to a series of case studies primarily focused on binding that are intended to illustrate the broad biological reach of equilibrium thinking in biology. These case studies include ligand-gated ion channels, thermodynamic models of transcription, and recent applications to the problem of bacterial chemotaxis. As part of the description of these case studies, we explore a number of different uses of the famed Monod–Wyman–Changeux (MWC) model as a generic tool for providing a mathematical characterization of two-state systems. These case studies should provide a template for tailoring equilibrium ideas to other problems of biological interest. PMID:21333788

  6. Vibrations, Quanta and Biology

    CERN Document Server

    Huelga, S F

    2013-01-01

    Quantum biology is an emerging field of research that concerns itself with the experimental and theoretical exploration of non-trivial quantum phenomena in biological systems. In this tutorial overview we aim to bring out fundamental assumptions and questions in the field, identify basic design principles and develop a key underlying theme -- the dynamics of quantum dynamical networks in the presence of an environment and the fruitful interplay that the two may enter. At the hand of three biological phenomena whose understanding is held to require quantum mechanical processes, namely excitation and charge transfer in photosynthetic complexes, magneto-reception in birds and the olfactory sense, we demonstrate that this underlying theme encompasses them all, thus suggesting its wider relevance as an archetypical framework for quantum biology.

  7. EDITORIAL: Physical Biology

    Science.gov (United States)

    Roscoe, Jane

    2004-06-01

    Physical Biology is a new peer-reviewed publication from Institute of Physics Publishing. Launched in 2004, the journal will foster the integration of biology with the traditionally more quantitative fields of physics, chemistry, computer science and other math-based disciplines. Its primary aim is to further the understanding of biological systems at all levels of complexity, ranging from the role of structure and dynamics of a single molecule to cellular networks and organisms. The journal encourages the development of a new biology-driven physics based on the extraordinary and increasingly rich data arising in biology, and provides research directions for those involved in the creation of novel bio-engineered systems. Physical Biology will publish a stimulating combination of full length research articles, communications, perspectives, reviews and tutorials from a wide range of disciplines covering topics such as: Single-molecule studies and nanobiotechnology Molecular interactions and protein folding Charge transfer and photobiology Ion channels; structure, function and ion regulation Molecular motors and force generation Subcellular processes Biological networks and neural systems Modeling aspects of molecular and cell biology Cell-cell signaling and interaction Biological patterns and development Evolutionary processes Novel tools and methods in physical biology Experts in the areas encompassed by the journal's scope have been appointed to the Editorial Scientific Committee and the composition of the Committee will be updated regularly to reflect the developments in this new and exciting field. Physical Biology is free online to everyone in 2004; you are invited to take advantage of this offer by visiting the journal homepage at http://physbio.iop.org This special print edition of Physical Biology is a combination of issues 1 and 2 of this electronic-only journal and it brings together an impressive range of articles in the fields covered, including a popular

  8. Multiscale Biological Materials

    DEFF Research Database (Denmark)

    Frølich, Simon

    2016-01-01

    Materials formed by organisms, also known as biological materials, exhibit outstanding structural properties. The range of materials formed in nature is remarkable and their functions include support, protection, motion, sensing, storage, and maintenance of physiological homeostasis. These complex...... materials are characterized by their hierarchical and composite design, where features with sizes ranging from nanometers to centimeters provide the basis for the functionality of the material. Understanding of biological materials is, while very interesting from a basic research perspective, also valuable...... as inspiration for the development of new materials for medical and technological applications. In order to successfully mimic biological materials we must first have a thorough understanding of their design. As such, the purpose of the characterization of biological materials can be defined as the establishment...

  9. Synthetic biology: A foundation for multi-scale molecular biology

    OpenAIRE

    Bower, Adam G; McClintock, Maria K; Stephen S. Fong

    2010-01-01

    The field of synthetic biology has made rapid progress in a number of areas including method development, novel applications and community building. In seeking to make biology “engineerable,” synthetic biology is increasing the accessibility of biological research to researchers of all experience levels and backgrounds. One of the underlying strengths of synthetic biology is that it may establish the framework for a rigorous bottom-up approach to studying biology starting at the DNA level. Bu...

  10. Effective graph resistance

    NARCIS (Netherlands)

    Ellens, W.; Spieksma, F.M.; Mieghem, P. van; Jamakovic, A.; Kooij, R.E.

    2011-01-01

    This paper studies an interesting graph measure that we call the effective graph resistance. The notion of effective graph resistance is derived from the field of electric circuit analysis where it is defined as the accumulated effective resistance between all pairs of vertices. The objective of the

  11. Resisting Mind Control.

    Science.gov (United States)

    Anderson, Susan M.; Zimbardo, Philip G.

    1980-01-01

    Provides conceptual analyses of mind control techniques along with practical advice on how to resist these techniques. The authors stress that effective mind control stems more from everyday social relations than from exotic technological gimmicks. Suggestions are given for resisting persuasion, resisting systems, and challenging the system.…

  12. Noise in Biology

    OpenAIRE

    Tsimring, Lev S

    2014-01-01

    Noise permeates biology on all levels, from the most basic molecular, sub-cellular processes to the dynamics of tissues, organs, organisms, and populations. The functional roles of noise in biological processes can vary greatly. Along with standard, entropy-increasing effects of producing random mutations, diversifying phenotypes in isogenic populations, limiting information capacity of signaling relays, it occasionally plays more surprising constructive roles by accelerating the pace of evol...

  13. Synthetic biology and biosecurity.

    Science.gov (United States)

    Robienski, Jürgen; Simon, Jürgen

    2014-01-01

    This article discusses the conflict fields and legal questions of synthetic biology, esp. concerning biosecurity. A respective jurisprudential discussion has not taken place yet in Germany apart from few statements and recommendations. But in Germany, Europe and the USA, it is generally accepted that a broad discussion is necessary. This is esp. true for the question of biosecurity and the possible dangers arising from Synthetic Biology. PMID:25845204

  14. Systems cell biology.

    Science.gov (United States)

    Mast, Fred D; Ratushny, Alexander V; Aitchison, John D

    2014-09-15

    Systems cell biology melds high-throughput experimentation with quantitative analysis and modeling to understand many critical processes that contribute to cellular organization and dynamics. Recently, there have been several advances in technology and in the application of modeling approaches that enable the exploration of the dynamic properties of cells. Merging technology and computation offers an opportunity to objectively address unsolved cellular mechanisms, and has revealed emergent properties and helped to gain a more comprehensive and fundamental understanding of cell biology.

  15. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Animal & ... back Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products

  16. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... FDA Submit search Popular Content Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & ... by Product Area Product Areas back Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & ...

  17. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & ... Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products

  18. Resisting Organizational Change

    Directory of Open Access Journals (Sweden)

    Gunnar Andersson

    2015-03-01

    Full Text Available We are continuously reminded of how change induces controversy and resistance, regardless of support. We repeatedly experience resistance in difficulties of implementation, little progress, and poor results, rather than increased productivity as anticipated. In a detailed account of how change plays out, a mosaic of what resistance looks like emerges. The picture is both familiar and absolutely concrete, and challenges the structural assumptions and dichotomies on support and resistance in an organization. The findings invite technologies, people, actions, practices and materiality to the discussions on support and resistance.

  19. Predation and selection for antibiotic resistance in natural environments

    DEFF Research Database (Denmark)

    Leisner, Jørgen; Jørgensen, Niels O. G.; Middelboe, Mathias

    2016-01-01

    Genes encoding resistance to antibiotics appear, like the antibiotics themselves, to be ancient, originating long before the rise of the era of anthropogenic antibiotics. However, detailed understanding of the specific biological advantages of antibiotic resistance in natural environments is still...... lacking, thus limiting our efforts to prevent environmental influx of resistance genes. Here, we propose that antibiotic-resistant cells not only evade predation from antibiotic producers but also take advantage of nutrients released from cells that are killed by the antibiotic-producing bacteria. Thus......, predation is potentially an important mechanism for driving antibiotic resistance during slow or stationary phase of growth when nutrients are deprived. This adds to explain the ancient nature and widespread occurrence of antibiotic resistance in natural environments unaffected by anthropogenic antibiotics...

  20. [Biologics and mycobacterial diseases].

    Science.gov (United States)

    Tsuyuguchi, Kazunari; Matsumoto, Tomoshige

    2013-03-01

    Various biologics such as TNF-alpha inhibitor or IL-6 inhibitor are now widely used for treatment of rheumatoid arthritis. Many reports suggested that one of the major issues is high risk of developing tuberculosis (TB) associated with using these agents, which is especially important in Japan where tuberculosis still remains endemic. Another concern is the risk of development of nontuberculous mycobacterial (NTM) diseases and we have only scanty information about it. The purpose of this symposium is to elucidate the role of biologics in the development of mycobacterial diseases and to establish the strategy to control them. First, Dr. Tohma showed the epidemiologic data of TB risks associated with using biologics calculated from the clinical database on National Database of Rheumatic Diseases by iR-net in Japan. He estimated TB risks in rheumatoid arthritis (RA) patients to be about four times higher compared with general populations and to become even higher by using biologics. He also pointed out a low rate of implementation of QuantiFERON test (QFT) as screening test for TB infection. Next, Dr. Tokuda discussed the issue of NTM disease associated with using biologics. He suggested the airway disease in RA patients might play some role in the development of NTM disease, which may conversely lead to overdiagnosis of NTM disease in RA patients. He suggested that NTM disease should not be uniformly considered a contraindication to treatment with biologics, considering from the results of recent multicenter study showing relatively favorable outcome of NTM patients receiving biologics. Patients with latent tuberculosis infection (LTBI) should receive LTBI treatment before starting biologics. Dr. Kato, a chairperson of the Prevention Committee of the Japanese Society for Tuberculosis, proposed a new LTBI guideline including active implementation of LTBI treatment, introducing interferon gamma release assay, and appropriate selection of persons at high risk for

  1. Biological Effects of Ionizing Radiation

    Science.gov (United States)

    Ingram, M.; Mason, W. B.; Whipple, G. H.; Howland, J. W.

    1952-04-07

    This report presents a review of present knowledge and concepts of the biological effects of ionizing radiations. Among the topics discussed are the physical and chemical effects of ionizing radiation on biological systems, morphological and physiological changes observed in biological systems subjected to ionizing radiations, physiological changes in the intact animal, latent changes following exposure of biological systems to ionizing radiations, factors influencing the biological response to ionizing radiation, relative effects of various ionizing radiations, and biological dosimetry.

  2. [Rodenticide resistance and consequences].

    Science.gov (United States)

    Esther, A; Endepols, S; Freise, J; Klemann, N; Runge, M; Pelz, H-J

    2014-05-01

    Resistance to anticoagulant rodenticides, such as warfarin was first described in 1958. Polymorphisms in the vitamin K epoxide reductase complex subunit 1 (VKORC1) gene and respective substitutions of amino acids in the VKOR enzyme are the major cause for rodenticide resistance. Resistant Norway rats in Germany are characterized by the Tyr139Cys genotype, which is spread throughout the northwest of the country. Resistant house mice with the VKOR variants Tyr139Cys, Leu128Ser and Arg12Trp/Ala26Ser/Ala48Thr/Arg61Leu (spretus type) are distributed over a number of locations in Germany. Resistance can reduce management attempts with consequences for stored product protection, hygiene and animal health. Anticoagulants of the first generation (warfarin, chlorophacinone, coumatetralyl) as well as bromadiolone and difenacoum are not an option for the control of resistant Norway rats. The same applies for house mice whereby the tolerance to compounds can be different between local incidences. Due to the higher toxicity and tendency to persist, the most potent anticoagulant rodenticides brodifacoum, flocoumafen and difethialone should be applied but only where resistance is known. In other cases less toxic anticoagulants should be preferred for rodent management in order to mitigate environmental risks. Resistance effects of further VKOR polymorphisms and their combinations, the spread of resistant rats and conditions supporting and reducing resistance should be investigated in order to improve resistance management strategies. PMID:24781908

  3. 人大肠癌多药耐药细胞LoVo/5-FU的建立及其生物学特性的初步研究%Establishment of multidrug-resistant human colorectal cancer cell line LoVo/5-FU:a preliminary study of biological characterization

    Institute of Scientific and Technical Information of China (English)

    姚学清; 卿三华; 杨洋; 秦斌; 袁玮; 夏琼

    2001-01-01

    目的建立人大肠癌LoVo细胞多药耐药细胞株LoVo/5-FU,并探讨其生物学特性及耐药机制。方法人大肠癌细胞系LoVo在体外经2.5μg/ml5-氟尿嘧啶(5-FU)作用,成功诱导LoVo/5-FU耐药细胞株。体外细胞毒性实验观察它们对5-FU、丝裂酶素(MMC)、阿霉素(ADM)、顺铂(DDP)、氨甲喋呤(MTX)和阿糖胞苷(AraC)等6种药物的敏感性。用噻唑蓝(MTT)法、光镜及扫描电镜观察两种细胞形态及结构并绘制出细胞体外生长曲线。免疫组化LSAB法检测细胞中P26-Bcl-2的表达。应用原位DNA末端转移酶标记法检测5-FU在两种细胞中诱导的细胞凋亡。结果LoVo/5-FU细胞株对5-FU、MMC和ADM均有耐药性,且对5-FU的耐药程度较亲本细胞提高。与亲本细胞相比,耐药细胞株生长慢,倍增期延长,汇合密度低,异型性明显。免疫组化LSAB法提示,LoVo/5-FU细胞的凋亡与P26-Bcl-2过度表达有关。LoVo细胞原位DNA末端转移酶标记阳性率高于LoVo/5-FU。结论LoVo/5-FU多药耐药细胞株耐药性稳定,在相同条件下与敏感细胞株LoVo相比,细胞凋亡受到抑制,提示LoVo/5-FU细胞可抵抗5-FU诱导的细胞凋亡,其机制可能与P26-Bcl-2过度表达密切相关。%Objective To investigate the changes in biological properties ofthe multidrug-resistant (MDR) variant of human colorectal cancer LoVo cell lines and to explore the mechanism for MDR generation in human colorectal cancer cells. Method A MDR variant of human colorectal cancer to 5-FU treatment, LoVo/5-FU, was established in vitro by exposing parent LoVo cells to pulse treatment with 2.5 μg/ml 5-FU over a period of 6 months. Its sensitivity to 6 antitumor agents was observed by MTT method, and morphological observation under light microscope and electron microscope of both LoVo and LoVo/5-FU cells were performed. Bcl-2 gene expressions in two cells were assayed immunohischemically. Results The Lo

  4. Spectacles of resistance and resistance of spectacles

    OpenAIRE

    Gabriel, Yiannis

    2008-01-01

    This paper explores organizational controls in an era dominated by spectacles, images and pictures and seeks to identify some forms of resistance that subvert and undermine these controls. It develops the metaphor of today’s organizations a ‘glass cages’ in juxtaposition to the Weberian ‘iron cages’ that summed up some of the qualities of organizations of yesteryear. The paper analyses new forms of resistance, such as whistleblowing and subvertizing, that are particularly aimed at besmirching...

  5. Genetics of metabolic resistance.

    Science.gov (United States)

    Richter, Otto; Langemann, Dirk; Beffa, Roland

    2016-09-01

    Herbicide resistance has become a major issue for many weeds. Metabolic resistance refers to the biochemical processes within organisms that degrade herbicides to less toxic compounds, resulting in a shift of the dose response curve. This type of resistance involves polygenic inheritance. A model is presented linking the biochemical pathway of amino acid synthesis and the detoxifying pathway of an inhibitor of the key enzyme ALS. From this model, resistance factors for each biotype are derived, which are then applied to a polygenic population genetic model for an annual weed plant. Polygenic inheritance is described by a new approach based on tensor products of heredity matrices. Important results from the model are that low dose regimes favour fast emergence of resistant biotypes and that the emergence of resistant biotypes occurs as abrupt outbreaks. The model is used to evaluate strategies for the management of metabolic resistance. PMID:27424952

  6. Magnetic biosensor system to detect biological targets

    KAUST Repository

    Li, Fuquan

    2012-09-01

    Magneto-resistive sensors in combination with magnetic beads provide sensing platforms, which are small in size and highly sensitive. These platforms can be fully integrated with microchannels and electronics to enable devices capable of performing complex tasks. Commonly, a sandwich method is used that requires a specific coating of the sensor\\'s surface to immobilize magnetic beads and biological targets on top of the sensor. This paper concerns a micro device to detect biological targets using magnetic concentration, magnetic as well as mechanical trapping and magnetic sensing. Target detection is based on the size difference between bare magnetic beads and magnetic beads with targets attached. This method remedies the need for a coating layer and reduces the number of steps required to run an experiment. © 2012 IEEE.

  7. Biologically Inspired Mushroom-Shaped Adhesive Microstructures

    Science.gov (United States)

    Heepe, Lars; Gorb, Stanislav N.

    2014-07-01

    Adhesion is a fundamental phenomenon with great importance in technology, in our everyday life, and in nature. In this article, we review physical interactions that resist the separation of two solids in contact. By using examples of biological attachment systems, we summarize and categorize various principles that contribute to the so-called gecko effect. Emphasis is placed on the contact geometry and in particular on the mushroom-shaped geometry, which is observed in long-term biological adhesive systems. Furthermore, we report on artificial model systems with this bio-inspired geometry and demonstrate that surface microstructures with this geometry are promising candidates for technical applications, in which repeatable, reversible, and residue-free adhesion under different environmental conditions—such as air, fluid, and vacuum—is required. Various applications in robotic systems and in industrial pick-and-place processes are discussed.

  8. Biological degradation of heavy mineral soaps

    Energy Technology Data Exchange (ETDEWEB)

    Glombitza, F.; Iske, U.; Bullmann, M.

    1988-11-01

    The possibility of biological degradation is exemplified by a chemically highly resistant Zircon mineral of the heavy mineral soaps of the Baltic Sea, with the aid of Thiobacillus ferrooxidans and Acetobacter spec. strains. The total matrix of the mineral is dissolved and all trace elements contained are solubilized. The different mechanisms of the leaching reaction give different distributions of the dissolved compounds in the phases of the leaching system. Concerning the REE a selectivity based on their physical characteristics is observed. There is a preferential solution of the light REE as compared to the heavy REE. The conditions of use are discussed.

  9. Onchocerciasis control: biological research is still needed

    Directory of Open Access Journals (Sweden)

    Boussinesq M.

    2008-09-01

    Full Text Available Achievements obtained by the onchocerciasis control programmes should not lead to a relaxation in the biological research on Onchocerca volvulus. Issues such as the Loa loa-related postivermectin serious adverse events, the uncertainties as to whether onchocerciasis can be eliminated by ivermectin treatments, and the possible emergence of ivermectin-resistant O. volvulus populations should be addressed proactively. Doxycycline, moxidectin and emodepside appear to be promising as alternative drugs against onchocerciasis but support to researches in immunology and genomics should also be increased to develop new control tools, including both vaccines and macrofilaricidal drugs.

  10. Stochastic Methods in Biology

    CERN Document Server

    Kallianpur, Gopinath; Hida, Takeyuki

    1987-01-01

    The use of probabilistic methods in the biological sciences has been so well established by now that mathematical biology is regarded by many as a distinct dis­ cipline with its own repertoire of techniques. The purpose of the Workshop on sto­ chastic methods in biology held at Nagoya University during the week of July 8-12, 1985, was to enable biologists and probabilists from Japan and the U. S. to discuss the latest developments in their respective fields and to exchange ideas on the ap­ plicability of the more recent developments in stochastic process theory to problems in biology. Eighteen papers were presented at the Workshop and have been grouped under the following headings: I. Population genetics (five papers) II. Measure valued diffusion processes related to population genetics (three papers) III. Neurophysiology (two papers) IV. Fluctuation in living cells (two papers) V. Mathematical methods related to other problems in biology, epidemiology, population dynamics, etc. (six papers) An important f...

  11. Biological races in humans.

    Science.gov (United States)

    Templeton, Alan R

    2013-09-01

    Races may exist in humans in a cultural sense, but biological concepts of race are needed to access their reality in a non-species-specific manner and to see if cultural categories correspond to biological categories within humans. Modern biological concepts of race can be implemented objectively with molecular genetic data through hypothesis-testing. Genetic data sets are used to see if biological races exist in humans and in our closest evolutionary relative, the chimpanzee. Using the two most commonly used biological concepts of race, chimpanzees are indeed subdivided into races but humans are not. Adaptive traits, such as skin color, have frequently been used to define races in humans, but such adaptive traits reflect the underlying environmental factor to which they are adaptive and not overall genetic differentiation, and different adaptive traits define discordant groups. There are no objective criteria for choosing one adaptive trait over another to define race. As a consequence, adaptive traits do not define races in humans. Much of the recent scientific literature on human evolution portrays human populations as separate branches on an evolutionary tree. A tree-like structure among humans has been falsified whenever tested, so this practice is scientifically indefensible. It is also socially irresponsible as these pictorial representations of human evolution have more impact on the general public than nuanced phrases in the text of a scientific paper. Humans have much genetic diversity, but the vast majority of this diversity reflects individual uniqueness and not race. PMID:23684745

  12. Identification of Bacteria and Determination of Biological Indicators

    Science.gov (United States)

    Venkateswaran, Kasthuri; La Duc, Myron T.; Vaishampayan, Parag A.

    2009-01-01

    The ultimate goal of planetary protection research is to develop superior strategies for inactivating resistance bearing micro-organisms like Rummeli - bacillus stabekisii. By first identifying the particular physiologic pathway and/or structural component of the cell/spore that affords it such elevated tolerance, eradication regimes can then be designed to target these resistance-conferring moieties without jeopardizing the structural integrity of spacecraft hardware. Furthermore, hospitals and government agencies frequently use biological indicators to ensure the efficacy of a wide range of sterilization processes. The spores of Rummelibacillus stabekisii, which are far more resistant to many of such perturbations, could likely serve as a more significant biological indicator for potential survival than those being used currently.

  13. Resistance reduction by bionic coupling of the earthworm lubrication function

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Based on the biological coupling theory, the resistance reduction characteristic of the surface morphology and surface wettability of the earthworm were studied in this paper. The parameters of surface dorsal pore and corrugation were extracted. According to these parameters, the lubrication mechanism of the earthworm surface was analyzed. The distribution of the pores and surface morphology were designed and the bionic coupling samples were prepared. The positive pressure, lubricant flow rate and advancing velocity were selected as the experiment factors while the soil friction resistance as observed object. According to the obtained data of bionic coupling samples from the testing system of biologic signal for tiny soil adhesion test, the optimal samples from the bionic coupling resistance reduction tests were selected through the range analysis. Compared to the normal ones, the soil resistance of bionic coupling samples was reduced by 76.8%. This is of great significance and offers bright prospects for reducing energy loss in terrain mechanics.

  14. Synthetic biology: Novel approaches for microbiology.

    Science.gov (United States)

    Padilla-Vaca, Felipe; Anaya-Velázquez, Fernando; Franco, Bernardo

    2015-06-01

    In the past twenty years, molecular genetics has created powerful tools for genetic manipulation of living organisms. Whole genome sequencing has provided necessary information to assess knowledge on gene function and protein networks. In addition, new tools permit to modify organisms to perform desired tasks. Gene function analysis is speed up by novel approaches that couple both high throughput data generation and mining. Synthetic biology is an emerging field that uses tools for generating novel gene networks, whole genome synthesis and engineering. New applications in biotechnological, pharmaceutical and biomedical research are envisioned for synthetic biology. In recent years these new strategies have opened up the possibilities to study gene and genome editing, creation of novel tools for functional studies in virus, parasites and pathogenic bacteria. There is also the possibility to re-design organisms to generate vaccine subunits or produce new pharmaceuticals to combat multi-drug resistant pathogens. In this review we provide our opinion on the applicability of synthetic biology strategies for functional studies of pathogenic organisms and some applications such as genome editing and gene network studies to further comprehend virulence factors and determinants in pathogenic organisms. We also discuss what we consider important ethical issues for this field of molecular biology, especially for potential misuse of the new technologies.

  15. Biology & control of Anopheles culicifacies Giles 1901.

    Science.gov (United States)

    Sharma, V P; Dev, V

    2015-05-01

    Malaria epidemiology is complex due to multiplicity of disease vectors, sibling species complex and variations in bionomical characteristics, vast varied terrain, various ecological determinants. There are six major mosquito vector taxa in India, viz. Anopheles culicifacies, An. fluviatilis, An. stephensi, An. minimus, An. dirus and An. sundaicus. Among these, An. culicifacies is widely distributed and considered the most important vector throughout the plains and forests of India for generating bulk of malaria cases (>60% annually). Major malaria epidemics are caused by An. culicifaices. It is also the vector of tribal malaria except parts of Odisha and Northeastern States of India. An. culicifacies has been the cause of perennial malaria transmission in forests, and over the years penetrated the deforested areas of Northeast. An. culicifacies participates in malaria transmission either alone or along with An. stephensi or An. fluviatilis. The National Vector Borne Disease Control Programme (NVBDCP) spends about 80 per cent malaria control budget annually in the control of An. culicifacies, yet it remains one of the most formidable challenges in India. With recent advances in molecular biology there has been a significant added knowledge in understanding the biology, ecology, genetics and response to interventions, requiring stratification for cost-effective and sustainable malaria control. Research leading to newer interventions that are evidence-based, community oriented and sustainable would be useful in tackling the emerging challenges in malaria control. Current priority areas of research should include in-depth vector biology and control in problem pockets, preparation of malaria-risk maps for focused and selective interventions, monitoring insecticide resistance, cross-border initiative and data sharing, and coordinated control efforts for achieving transmission reduction, and control of drug-resistant malaria. The present review on An. culicifacies

  16. Informing Biological Design by Integration of Systems and Synthetic Biology

    OpenAIRE

    Smolke, Christina D.; Silver, Pamela A.

    2011-01-01

    Synthetic biology aims to make the engineering of biology faster and more predictable. In contrast, systems biology focuses on the interaction of myriad components and how these give rise to the dynamic and complex behavior of biological systems. Here, we examine the synergies between these two fields.

  17. Biological therapy of psoriasis

    Directory of Open Access Journals (Sweden)

    Sivamani Raja

    2010-01-01

    Full Text Available The treatment of psoriasis has undergone a revolution with the advent of biologic therapies, including infliximab, etanercept, adalimumab, efalizumab, and alefacept. These medications are designed to target specific components of the immune system and are a major technological advancement over traditional immunosuppressive medications. These usually being well tolerated are being found useful in a growing number of immune-mediated diseases, psoriasis being just one example. The newest biologic, ustekinumab, is directed against the p40 subunit of the IL-12 and IL-23 cytokines. It has provided a new avenue of therapy for an array of T-cell-mediated diseases. Biologics are generally safe; however, there has been concern over the risk of lymphoma with use of these agents. All anti-TNF-α agents have been associated with a variety of serious and "routine" opportunistic infections.

  18. Epigenetics: Biology's Quantum Mechanics.

    Science.gov (United States)

    Jorgensen, Richard A

    2011-01-01

    The perspective presented here is that modern genetics is at a similar stage of development as were early formulations of quantum mechanics theory in the 1920s and that in 2010 we are at the dawn of a new revolution in genetics that promises to enrich and deepen our understanding of the gene and the genome. The interrelationships and interdependence of two views of the gene - the molecular biological view and the epigenetic view - are explored, and it is argued that the classical molecular biological view is incomplete without incorporation of the epigenetic perspective and that in a sense the molecular biological view has been evolving to include the epigenetic view. Intriguingly, this evolution of the molecular view toward the broader and more inclusive epigenetic view of the gene has an intriguing, if not precise, parallel in the evolution of concepts of atomic physics from Newtonian mechanics to quantum mechanics that are interesting to consider. PMID:22639577

  19. Epigenetics: Biology's Quantum Mechanics

    Directory of Open Access Journals (Sweden)

    Richard A Jorgensen

    2011-04-01

    Full Text Available The perspective presented here is that modern genetics is at a similar stage of development as were early formulations of quantum mechanics theory in the 1920's and that in 2010 we are at the dawn of a new revolution in genetics that promises to enrich and deepen our understanding of the gene and the genome. The interrelationships and interdependence of two views of the gene - the molecular biological view and the epigenetic view - are explored, and it is argued that the classical molecular biological view is incomplete without incorporation of the epigenetic perspective and that in a sense the molecular biological view has been evolving to include the epigenetic view. Intriguingly, this evolution of the molecular view toward the broader and more inclusive epigenetic view of the gene has an intriguing, if not precise, parallel in the evolution of concepts of atomic physics from Newtonian mechanics to quantum mechanics that are interesting to consider.

  20. The biology of personality.

    Science.gov (United States)

    Mulder, R

    1992-09-01

    Historically, models of personality have generally postulated, or assumed, a link with biology. This century has witnessed a major revision of these ideas with both behavioural and psychoanalytic theorists emphasising life experiences as being largely responsible for behaviour as adults. Challenges to this assumption of the overwhelming importance of life experiences are reviewed. An extensive body of data now exists suggesting that biology contributes significantly to individual variability. This biological contribution occurs at a relatively low level in the central nervous system, best defined as temperament. Further research has suffered from the lack of a cohesive psychobiological model. Cloninger's tridimensional theory of personality is presented as a model which attempts to bridge the gap between theoretical temperamental traits, neurotransmitter function and clinical psychiatry. It is to be hoped that new theoretical models will be formulated which will focus on the importance of temperamental variables in psychiatric disorders.

  1. Biological Soft Robotics.

    Science.gov (United States)

    Feinberg, Adam W

    2015-01-01

    In nature, nanometer-scale molecular motors are used to generate force within cells for diverse processes from transcription and transport to muscle contraction. This adaptability and scalability across wide temporal, spatial, and force regimes have spurred the development of biological soft robotic systems that seek to mimic and extend these capabilities. This review describes how molecular motors are hierarchically organized into larger-scale structures in order to provide a basic understanding of how these systems work in nature and the complexity and functionality we hope to replicate in biological soft robotics. These span the subcellular scale to macroscale, and this article focuses on the integration of biological components with synthetic materials, coupled with bioinspired robotic design. Key examples include nanoscale molecular motor-powered actuators, microscale bacteria-controlled devices, and macroscale muscle-powered robots that grasp, walk, and swim. Finally, the current challenges and future opportunities in the field are addressed.

  2. 7th Annual Systems Biology Symposium: Systems Biology and Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Galitski, Timothy P.

    2008-04-01

    Systems biology recognizes the complex multi-scale organization of biological systems, from molecules to ecosystems. The International Symposium on Systems Biology has been hosted by the Institute for Systems Biology in Seattle, Washington, since 2002. The annual two-day event gathers the most influential researchers transforming biology into an integrative discipline investingating complex systems. Engineering and application of new technology is a central element of systems biology. Genome-scale, or very small-scale, biological questions drive the enigneering of new technologies, which enable new modes of experimentation and computational analysis, leading to new biological insights and questions. Concepts and analytical methods in engineering are now finding direct applications in biology. Therefore, the 2008 Symposium, funded in partnership with the Department of Energy, featured global leaders in "Systems Biology and Engineering."

  3. Nanomedicinal strategies to treat multidrug-resistant tumors: current progress

    OpenAIRE

    Dong, Xiaowei; Mumper, Russell J.

    2010-01-01

    Multidrug resistance (MDR) is a major impediment to the success of cancer chemotherapy. P-glycoprotein is an important and the best-known membrane transporter involved in MDR. Several strategies have been used to address MDR, especially P-glycoprotein-mediated drug resistance in tumors. However, clinical success has been limited, largely due to issues regarding lack of efficacy and/or safety. Nanoparticles have shown the ability to target tumors based on their unique physical and biological p...

  4. Biological and Pharmaceutical Nanomaterials

    Science.gov (United States)

    Kumar, Challa S. S. R.

    2006-01-01

    This first comprehensive yet concise overview of all important classes of biological and pharmaceutical nanomaterials presents in one volume the different kinds of natural biological compounds that form nanomaterials or that may be used to purposefully create them. This unique single source of information brings together the many articles published in specialized journals, which often remain unseen by members of other, related disciplines. Covering pharmaceutical, nucleic acid, peptide and DNA-Chitosan nanoparticles, the book focuses on those innovative materials and technologies needed for the continued growth of medicine, healthcare, pharmaceuticals and human wellness. For chemists, biochemists, cell biologists, materials scientists, biologists, and those working in the pharmaceutical and chemical industries.

  5. Neutron structural biology

    International Nuclear Information System (INIS)

    Neutron structural biology will be one of the most important fields in the life sciences which will interest human beings in the 21st century because neutrons can provide not only the position of hydrogen atoms in biological macromolecules but also the dynamic molecular motion of hydrogen atoms and water molecules. However, there are only a few examples experimentally determined at present because of the lack of neutron source intensity. Next generation neutron source scheduled in JAERI (Performance of which is 100 times better than that of JRR-3M) opens the life science of the 21st century. (author)

  6. Chemical and Biological Kinetics

    Science.gov (United States)

    Emanuel', N. M.

    1981-10-01

    Examples of the application of the methods and ideas of chemical kinetics in various branches of chemistry and biology are considered and the results of studies on the kinetics and mechanisms of autoxidation and inhibited and catalysed oxidation of organic substances in the liquid phase are surveyed. Problems of the kinetics of the ageing of polymers and the principles of their stabilisation are discussed and certain trends in biological kinetics (kinetics of tumour growth, kinetic criteria of the effectiveness of chemotherapy, problems of gerontology, etc.) are considered. The bibliography includes 281 references.

  7. Networks in Cell Biology = Modelling cell biology with networks

    OpenAIRE

    Buchanan, Mark; Caldarelli, Guido; De Los Rios, Paolo; Rao, Francesco; Vendruscolo, M.

    2010-01-01

    The science of complex biological networks is transforming research in areas ranging from evolutionary biology to medicine. This is the first book on the subject, providing a comprehensive introduction to complex network science and its biological applications. With contributions from key leaders in both network theory and modern cell biology, this book discusses the network science that is increasingly foundational for systems biology and the quantitative understanding of living systems. It ...

  8. Chemical and biological metal nanoparticles as antimycobacterial agents: A comparative study.

    Science.gov (United States)

    Singh, Richa; Nawale, Laxman U; Arkile, Manisha; Shedbalkar, Utkarsha U; Wadhwani, Sweety A; Sarkar, Dhiman; Chopade, Balu A

    2015-08-01

    Resistance among mycobacteria leading to multidrug-resistant and extensively drug-resistant tuberculosis is a major threat. However, nanotechnology has provided new insights in drug delivery and medicine development. This is the first comparative report to determine the activity of chemically and biologically synthesised silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) against mycobacteria. Screening data revealed the high mycobactericidal efficiency of AgNPs, with minimum inhibitory concentrations (MICs) of therapeutics for tuberculosis.

  9. Systems biology in animal sciences

    NARCIS (Netherlands)

    Woelders, H.; Pas, te M.F.W.; Bannink, A.; Veerkamp, R.F.; Smits, M.A.

    2011-01-01

    Systems biology is a rapidly expanding field of research and is applied in a number of biological disciplines. In animal sciences, omics approaches are increasingly used, yielding vast amounts of data, but systems biology approaches to extract understanding from these data of biological processes an

  10. Challenges to Resistance Welding

    DEFF Research Database (Denmark)

    Song, Quanfeng

    simulation of resistance welding has been under development for many years. Yet it is no easy to make simulation results reliable and accurate because of the complexity of resistance welding process. In the 2nd part of the report numerical modeling of resistance welding is reviewed, some critical factors......This report originates from the compulsory defense during my Ph.D. study at the Technical University of Denmark. Resistance welding is an old and well-proven technology. Yet the emergence of more and more new materials, new designs, invention off new joining techniques, and more stringent...... requirement in quality have imposed challenges to the resistance welding. More some research and development have to be done to adapt the old technology to the manufacturing industry of the 21st century. In the 1st part of the report, the challenging factors to the resistance welding are reviewed. Numerical...

  11. Resistance to Bacillus thuringiensis Toxin Cry2Ab in Trichoplusia ni Is Conferred by a Novel Genetic Mechanism

    OpenAIRE

    Song, Xiaozhao; Kain, Wendy; Cassidy, Douglas; Wang, Ping

    2015-01-01

    The resistance to the Bacillus thuringiensis (Bt) toxin Cry2Ab in a greenhouse-originated Trichoplusia ni strain resistant to both Bt toxins Cry1Ac and Cry2Ab was characterized. Biological assays determined that the Cry2Ab resistance in the T. ni strain was a monogenic recessive trait independent of Cry1Ac resistance, and there existed no significant cross-resistance between Cry1Ac and Cry2Ab in T. ni. From the dual-toxin-resistant T. ni strain, a strain resistant to Cry2Ab only was isolated,...

  12. Management of resistant depression.

    OpenAIRE

    Warneke, L

    1996-01-01

    Treatment-resistant depression is a relative concept. It has been formally defined as a mood disorder that fails to respond to three adequate trials of antidepressants. However, treatment resistance is relative to the expertise and knowledge of the treating physician and the availability of resources, such as electroconvulsive therapy. Only about 7% of patients show absolute treatment resistance, and even they can be helped.

  13. Resistance to change

    OpenAIRE

    Dow, James; Perotti, Enrico

    2010-01-01

    Established firms often fail to maintain leadership following disruptive market shifts. We argue that such firms are more prone to internal resistance. A radical adjustment of assets affects the distribution of employee rents, creating winners and losers. Losers resist large changes when strong customer goodwill cushions the consequences. Partial adaptation may lead winners to depart to form new firms with no goodwill, but no internal resistance.

  14. Situeret interesse i biologi

    DEFF Research Database (Denmark)

    Dohn, Niels Bonderup

    2006-01-01

    Interesse hævdes at spille en vigtig rolle i læring. Med udgangspunkt i interesseteori og situeret læring har jeg foretaget et studium i en gymnasieklasse med biologi på højt niveau, med henblik på at identificere hvilke forhold der har betydning for hvad der fanger elevers interesse. Jeg har...

  15. Water pollution biology

    Energy Technology Data Exchange (ETDEWEB)

    Mason, C.F. [University of Essex, Colchester (United Kingdom). Dept. of Biology

    1996-12-31

    Chapter 4 of this book describes the effects of major types of pollutants on aquatic life. These are: organic pollution, eutrophication, acidification, toxic chemicals, oil, and radioactivity. The review includes an description of some of the methods of assessing the biological impacts of pollution. 50 refs., 8 figs., 3 tabs.

  16. Biology Curriculum Support Document.

    Science.gov (United States)

    North Carolina Dept. of Public Instruction, Raleigh.

    This biology curriculum supplement includes the North Carolina Standard Course of Study Goals, helpful resources, and suggested activities supported by inquiry-based laboratory activities. Contents include a detailed description of content which provides the goals and standards being sough), a materials list for inquiry support labs and…

  17. Molecular Biology of Medulloblastoma

    OpenAIRE

    J Gordon Millichap

    2007-01-01

    Current methods of diagnosis and treatment of medulloblastoma, and the influence of new biological advances in the development of more effective and less toxic therapies are reviewed by researchers at Children’s National Medical Center, The George Washington University, Washington, DC.

  18. Bayes in biological anthropology.

    Science.gov (United States)

    Konigsberg, Lyle W; Frankenberg, Susan R

    2013-12-01

    In this article, we both contend and illustrate that biological anthropologists, particularly in the Americas, often think like Bayesians but act like frequentists when it comes to analyzing a wide variety of data. In other words, while our research goals and perspectives are rooted in probabilistic thinking and rest on prior knowledge, we often proceed to use statistical hypothesis tests and confidence interval methods unrelated (or tenuously related) to the research questions of interest. We advocate for applying Bayesian analyses to a number of different bioanthropological questions, especially since many of the programming and computational challenges to doing so have been overcome in the past two decades. To facilitate such applications, this article explains Bayesian principles and concepts, and provides concrete examples of Bayesian computer simulations and statistics that address questions relevant to biological anthropology, focusing particularly on bioarchaeology and forensic anthropology. It also simultaneously reviews the use of Bayesian methods and inference within the discipline to date. This article is intended to act as primer to Bayesian methods and inference in biological anthropology, explaining the relationships of various methods to likelihoods or probabilities and to classical statistical models. Our contention is not that traditional frequentist statistics should be rejected outright, but that there are many situations where biological anthropology is better served by taking a Bayesian approach. To this end it is hoped that the examples provided in this article will assist researchers in choosing from among the broad array of statistical methods currently available.

  19. Openers for Biology Classes.

    Science.gov (United States)

    Gridley, C. Robert R.

    This teaching guide contains 200 activities that are suitable for openers and demonstrations in biology classes. Details are provided regarding the use of these activities. Some of the broad topics under which the activities are organized include algae, amphibians, bacteria, biologists, crustaceans, dinosaurs, ecology, evolution, flowering plants,…

  20. Biological response modifiers

    Energy Technology Data Exchange (ETDEWEB)

    Weller, R.E.

    1991-10-01

    Much of what used to be called immunotherapy is now included in the term biological response modifiers. Biological response modifiers (BRMs) are defined as those agents or approaches that modify the relationship between the tumor and host by modifying the host's biological response to tumor cells with resultant therapeutic effects.'' Most of the early work with BRMs centered around observations of spontaneous tumor regression and the association of tumor regression with concurrent bacterial infections. The BRM can modify the host response in the following ways: Increase the host's antitumor responses through augmentation and/or restoration of effector mechanisms or mediators of the host's defense or decrease the deleterious component by the host's reaction; Increase the host's defenses by the administration of natural biologics (or the synthetic derivatives thereof) as effectors or mediators of an antitumor response; Augment the host's response to modified tumor cells or vaccines, which might stimulate a greater response by the host or increase tumor-cell sensitivity to an existing response; Decrease the transformation and/or increase differentiation (maturation) of tumor cells; or Increase the ability of the host to tolerate damage by cytotoxic modalities of cancer treatment.

  1. Next-generation biology

    DEFF Research Database (Denmark)

    Rodrigues da Fonseca, Rute Andreia; Albrechtsen, Anders; Themudo, Gonçalo Espregueira;

    2016-01-01

    we present an overview of the current sequencing technologies and the methods used in typical high-throughput data analysis pipelines. Subsequently, we contextualize high-throughput DNA sequencing technologies within their applications in non-model organism biology. We include tips regarding managing...

  2. Biological Warfare Agents

    Directory of Open Access Journals (Sweden)

    Dev Vrat Kamboj

    2006-10-01

    Full Text Available There is a long historic record of use of biological warfare (BW agents by warring countriesagainst their enemies. However, the frequency of their use has increased since the beginningof the twentieth century. World war I witnessed the use of anthrax agent against human beingsand animals by Germans, followed by large-scale field trials by Japanese against war prisonersand Chinese population during world war II. Ironically, research and development in biologicalwarfare agents increased tremendously after the Geneva Protocol, signed in 1925, because ofits drawbacks which were overcome by Biological and Toxin Weapons Convention (BTWC in1972. Biological warfare programme took back seat after the 1972 convention but biologicalagents regained their importance after the bioterrorist attacks of anthrax powder in 2001. In thelight of these attacks, many of which turned out to be hoax, general awareness is required aboutbiological warfare agents that can be used against them. This review has been written highlightingimportant biological warfare agents, diseases caused by them, possible therapies and otherprotection measures.

  3. Nuclear physics and biology

    International Nuclear Information System (INIS)

    This paper is about nuclear instrumentation and biological concepts, based on images from appropriate Β detectors. First, three detectors are described: the SOFI detector, for gene mapping, the SOFAS detector, for DNA sequencing and the RIHR detector, for in situ hybridization. Then, the paper presents quantitative imaging in molecular genetic and functional imaging. (TEC)

  4. Antiprotons get biological

    CERN Multimedia

    2003-01-01

    After its final run in September, the first results of the Antiproton Cell Experiment (ACE) look very promising. It was the first experiment to take data on the biological effects of antiproton beams to evaluate the potential of antiprotons in radiation therapy.

  5. Plant Systems Biology (editorial)

    Science.gov (United States)

    In June 2003, Plant Physiology published an Arabidopsis special issue devoted to plant systems biology. The intention of Natasha Raikhel and Gloria Coruzzi, the two editors of this first-of-its-kind issue, was ‘‘to help nucleate this new effort within the plant community’’ as they considered that ‘‘...

  6. Facts about Antibiotic Resistance

    Science.gov (United States)

    ... Recommendations Pediatric Treatment Recommendations Inpatient Healthcare Professionals Community Pharmacists Continuing Education & Curriculum Opportunities Weighing in on Antibiotic Resistance Improving Prescribing Outpatient Antibiotic Stewardship Interventions That Work Systematic Reviews ...

  7. Antibiotic / Antimicrobial Resistance Glossary

    Science.gov (United States)

    ... Recommendations Pediatric Treatment Recommendations Inpatient Healthcare Professionals Community Pharmacists Continuing Education & Curriculum Opportunities Weighing in on Antibiotic Resistance Improving Prescribing Outpatient Antibiotic Stewardship Interventions That Work Systematic Reviews ...

  8. Biological trade and markets.

    Science.gov (United States)

    Hammerstein, Peter; Noë, Ronald

    2016-02-01

    Cooperation between organisms can often be understood, like trade between merchants, as a mutually beneficial exchange of services, resources or other 'commodities'. Mutual benefits alone, however, are not sufficient to explain the evolution of trade-based cooperation. First, organisms may reject a particular trade if another partner offers a better deal. Second, while human trade often entails binding contracts, non-human trade requires unwritten 'terms of contract' that 'self-stabilize' trade and prevent cheating even if all traders strive to maximize fitness. Whenever trading partners can be chosen, market-like situations arise in nature that biologists studying cooperation need to account for. The mere possibility of exerting partner choice stabilizes many forms of otherwise cheatable trade, induces competition, facilitates the evolution of specialization and often leads to intricate forms of cooperation. We discuss selected examples to illustrate these general points and review basic conceptual approaches that are important in the theory of biological trade and markets. Comparing these approaches with theory in economics, it turns out that conventional models-often called 'Walrasian' markets-are of limited relevance to biology. In contrast, early approaches to trade and markets, as found in the works of Ricardo and Cournot, contain elements of thought that have inspired useful models in biology. For example, the concept of comparative advantage has biological applications in trade, signalling and ecological competition. We also see convergence between post-Walrasian economics and biological markets. For example, both economists and biologists are studying 'principal-agent' problems with principals offering jobs to agents without being sure that the agents will do a proper job. Finally, we show that mating markets have many peculiarities not shared with conventional economic markets. Ideas from economics are useful for biologists studying cooperation but need

  9. Biological trade and markets

    Science.gov (United States)

    2016-01-01

    Cooperation between organisms can often be understood, like trade between merchants, as a mutually beneficial exchange of services, resources or other ‘commodities’. Mutual benefits alone, however, are not sufficient to explain the evolution of trade-based cooperation. First, organisms may reject a particular trade if another partner offers a better deal. Second, while human trade often entails binding contracts, non-human trade requires unwritten ‘terms of contract’ that ‘self-stabilize’ trade and prevent cheating even if all traders strive to maximize fitness. Whenever trading partners can be chosen, market-like situations arise in nature that biologists studying cooperation need to account for. The mere possibility of exerting partner choice stabilizes many forms of otherwise cheatable trade, induces competition, facilitates the evolution of specialization and often leads to intricate forms of cooperation. We discuss selected examples to illustrate these general points and review basic conceptual approaches that are important in the theory of biological trade and markets. Comparing these approaches with theory in economics, it turns out that conventional models—often called ‘Walrasian’ markets—are of limited relevance to biology. In contrast, early approaches to trade and markets, as found in the works of Ricardo and Cournot, contain elements of thought that have inspired useful models in biology. For example, the concept of comparative advantage has biological applications in trade, signalling and ecological competition. We also see convergence between post-Walrasian economics and biological markets. For example, both economists and biologists are studying ‘principal–agent’ problems with principals offering jobs to agents without being sure that the agents will do a proper job. Finally, we show that mating markets have many peculiarities not shared with conventional economic markets. Ideas from economics are useful for biologists

  10. Biological trade and markets.

    Science.gov (United States)

    Hammerstein, Peter; Noë, Ronald

    2016-02-01

    Cooperation between organisms can often be understood, like trade between merchants, as a mutually beneficial exchange of services, resources or other 'commodities'. Mutual benefits alone, however, are not sufficient to explain the evolution of trade-based cooperation. First, organisms may reject a particular trade if another partner offers a better deal. Second, while human trade often entails binding contracts, non-human trade requires unwritten 'terms of contract' that 'self-stabilize' trade and prevent cheating even if all traders strive to maximize fitness. Whenever trading partners can be chosen, market-like situations arise in nature that biologists studying cooperation need to account for. The mere possibility of exerting partner choice stabilizes many forms of otherwise cheatable trade, induces competition, facilitates the evolution of specialization and often leads to intricate forms of cooperation. We discuss selected examples to illustrate these general points and review basic conceptual approaches that are important in the theory of biological trade and markets. Comparing these approaches with theory in economics, it turns out that conventional models-often called 'Walrasian' markets-are of limited relevance to biology. In contrast, early approaches to trade and markets, as found in the works of Ricardo and Cournot, contain elements of thought that have inspired useful models in biology. For example, the concept of comparative advantage has biological applications in trade, signalling and ecological competition. We also see convergence between post-Walrasian economics and biological markets. For example, both economists and biologists are studying 'principal-agent' problems with principals offering jobs to agents without being sure that the agents will do a proper job. Finally, we show that mating markets have many peculiarities not shared with conventional economic markets. Ideas from economics are useful for biologists studying cooperation but need

  11. Fitness cost of VanA-type vancomycin resistance in methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Foucault, Marie-Laure; Courvalin, Patrice; Grillot-Courvalin, Catherine

    2009-06-01

    We have quantified the biological cost of VanA-type glycopeptide resistance due to the acquisition of the resistance operon by methicillin-resistant Staphylococcus aureus (MRSA) from Enterococcus sp. Exponential growths of recipient strain HIP11713, its transconjugant VRSA-1, VRSA-5, and VRSA-6 were compared in the absence or, except for HIP11713, in the presence of vancomycin. Induction of resistance was performed by adding vancomycin in both the preculture and the culture or the culture at only 1/50 the MIC. In the absence of vancomycin, the growth rates of the vancomycin-resistant S. aureus (VRSA) strains were similar to that of susceptible MRSA strain HIP11713. When resistance was induced, and under both conditions, there was a significant reduction of the growth rate of the VRSA strains relative to that of HIP11713 and to those of their noninduced counterparts, corresponding to a ca. 20% to 38% reduction in fitness. Competition experiments between isogenic VRSA-1 and HIP11713 mixed at a 1:1, 1:100, or 100:1 ratio revealed a competitive disadvantage of 0.4% to 3% per 10 generations of the transconjugant versus the recipient. This slight fitness burden can be attributed to the basal level of expression of the van genes in the absence of induction combined with a gene dosage effect due to the presence of the van operon on multicopy plasmids. These data indicate that VanA-type resistance, when induced, is highly costly for the MRSA host, whereas in the absence of induction, its biological cost is minimal. Thus, the potential for the dissemination of VRSA clinical isolates should not be underestimated.

  12. Systems biology, emergence and antireductionism.

    Science.gov (United States)

    Kesić, Srdjan

    2016-09-01

    This study explores the conceptual history of systems biology and its impact on philosophical and scientific conceptions of reductionism, antireductionism and emergence. Development of systems biology at the beginning of 21st century transformed biological science. Systems biology is a new holistic approach or strategy how to research biological organisms, developed through three phases. The first phase was completed when molecular biology transformed into systems molecular biology. Prior to the second phase, convergence between applied general systems theory and nonlinear dynamics took place, hence allowing the formation of systems mathematical biology. The second phase happened when systems molecular biology and systems mathematical biology, together, were applied for analysis of biological data. Finally, after successful application in science, medicine and biotechnology, the process of the formation of modern systems biology was completed. Systems and molecular reductionist views on organisms were completely opposed to each other. Implications of systems and molecular biology on reductionist-antireductionist debate were quite different. The analysis of reductionism, antireductionism and emergence issues, in the era of systems biology, revealed the hierarchy between methodological, epistemological and ontological antireductionism. Primarily, methodological antireductionism followed from the systems biology. Only after, epistemological and ontological antireductionism could be supported.

  13. Relations between Intuitive Biological Thinking and Biological Misconceptions in Biology Majors and Nonmajors

    OpenAIRE

    Coley, John D.; Tanner, Kimberly

    2015-01-01

    Research and theory development in cognitive psychology and science education research remain largely isolated. Biology education researchers have documented persistent scientifically inaccurate ideas, often termed misconceptions, among biology students across biological domains. In parallel, cognitive and developmental psychologists have described intuitive conceptual systems—teleological, essentialist, and anthropocentric thinking—that humans use to reason about biology. We hypothesize that...

  14. 下调MTRR基因表达对顺铂耐药的卵巢上皮性癌SKOV3细胞体内外生物学特性的影响%Biological effect of down-regulating of MTRR gene on cisplatin-resistant ovarian cancer SKOV3 cells in vitro and in vivo studies

    Institute of Scientific and Technical Information of China (English)

    陈佳; 王琪; 张玮; 李力

    2016-01-01

    Objective To study the biological effects of down-regulatingof methionine synthase reductase (MTRR) gene on cisplatin resistant ovarian cancer SKOV3/DDP cell in vitro and in vivo. Methods (1) Establishing the cell line of MTRR down-regulated. Four short hairpin RNA (shRNA) for MTRR gene (U6-GFP-Neo-homo-1106, U6-GFP-Neo-homo-1931, U6-GFP-Neo-homo-419, U6-GFP-Neo-homo-1460) were designed respectively. Western blot was used to detect the interference efficiency and selected the most efficient shRNA. The MTRR 1106 was selected as the best silencing effect of interference fragment and then therecombinant plasmid vector pSicoR-1106 was constructed and transfected into SKOV3/DDP cells.The stably transfected cells was obtained by screening of flow cytometry(FCM).Fluorescence quantitative reverse transcription (RT)-PCR and western blot were used to detect the expression of MTRR mRNA and protein. (2) Study in vitro: recombinant plasmid expression vector pSicoR-1106, pSicoR-NC and packaging plasmid were respectively transfected into 293T cell. SKOV3/DDP cells were transfected by viral supernatant. The experiment was divided into three groups, namely SKOV3/DDP-MTRRi (down-regulated MTRR group), SKOV3/DDP-NC (negative control group), and the SKOV3/DDP (blank control group). The cell growth curves and half maximal inhibitory concentration (IC50) of cisplatin were made by methyl thiazolyl tetrazolium (MTT) method. Three groups cells were treated with different concentration of cisplatin (0, 1, 2 and 4 μg/ml). The clonogenicity efficiency was observed by clony formation test. The cell cycles were measured by FCM . (3) Study in vivo: three groups cells were subcutaneously inoculated into the nude mice to develop a tumor model. Mice were injected intraperitoneally with cisplatin at 2.5 mg/kg (once every 2 days, in 21 rounds), then the tumor growth was observed. The expression of MTRR and proliferation-related Ki-67 antigen by immunohistochemistry in xenograft tumors were measured

  15. Methods to predict antibiotic resistance: From genes to metagenomes

    OpenAIRE

    Lira, Felipe

    2015-01-01

    Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 21-10-2015 As many antibiotics exist as many mechanisms of resistance will rise. Antibiotic resistance is a worldwide problem and deserves all sort of attention and dedication to identify the critical points which might promote or facilitate the emergence of novel resistance genes in one community, as well the propagation of the already kno...

  16. Lymphocyte glucocorticoid receptor resistance and depressive symptoms severity : A preliminary report

    NARCIS (Netherlands)

    Tanke, M. A. C.; Bosker, F. J.; Gladkevich, An.; Medema, H. M.; den Boer, J. A.; Korf, J.

    2008-01-01

    Objective: Assessment of the temporal interrelationship of neuropsychiatric parameters requires technologies allowing frequent biological measurements. We propose glucocorticoid receptor (GR) function of lymphocytes to assess the temporal relationship between glucocorticoid resistance and the course

  17. Biological heterogeneity of cancer

    OpenAIRE

    Isaiah J. Fidler

    2012-01-01

    Despite significant improvements in diagnosis, surgical techniques, and advancements in general patient care, the majority of deaths from cancer are caused by the continuous growth of metastases that are resistant to conventional therapies. In a large number of cancer patients, metastasis may well have occurred by the time of diagnosis. The metastases can be located in different distant organs and in different regions within a single organ. The major obstacle for the eradication of metastases...

  18. Resistance to change

    NARCIS (Netherlands)

    J. Dow; E. Perotti

    2013-01-01

    Established firms often fail to maintain leadership following disrup tive market shifts. We argue that such firms are more prone to internal resistance. A radical adjustment of assets affects the distribution of employee rents, creating winners and losers. Losers resist large changes when strong cus

  19. Resistance to change

    NARCIS (Netherlands)

    J. Dow; E. Perotti

    2009-01-01

    Established firms often fail to maintain leadership following disruptive market shifts. We argue that such firms are more prone to internal resistance. A radical adjustment of assets affects the distribution of employee rents, creating winners and losers. Losers resist large changes when strong cust

  20. African Women Writing Resistance

    Institute of Scientific and Technical Information of China (English)

    Jennifer Browdy de Hernandez; Pauline Dongala; Omotayo; Jolaosho; Anne Serafin

    2011-01-01

    AFRICAN Women Writing Resistance is the first transnational anthology to focus on women's strategies of resistance to the challenges they face in Africa today.The anthology brings together personal narratives,testimony,interviews,short stories,poetry,performance scripts,folktales and lyrics.

  1. African Women Writing Resistance

    Institute of Scientific and Technical Information of China (English)

    Jennifer; Browdy; de; Hernandez; Pauline; Dongala; Omotayo; Jolaosho; Anne; Serafin

    2011-01-01

    An Anthology of Contemporary Voices AFRICAN Women Writing Resistance is the first transnational anthology to focus on women’s strategies of resistance to the challenges they face in Africa today.The anthology brings together personal narratives,testimony,interviews, short stories,po-

  2. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Translation - Animation of Antimicrobial Resistance (WMV - 19.2MB) Chinese Translation - Animation of Antimicrobial Resistance (WMV - 19.2MB) ... FEAR Act Site Map Transparency Website Policies U.S. Food and Drug Administration 10903 New Hampshire Avenue Silver ...

  3. Resistance and conformity

    NARCIS (Netherlands)

    S.R. Sumter; C.L. Bokhorst; P.M. Westenberg

    2011-01-01

    Resistance to peer influence, or the ability to resist making choices or adopting views under the implicit or explicit influence of your peers, is expected to undergo changes during adolescence. Two developmental trajectories have emerged from the field. On the one hand, adolescents show a temporary

  4. Glycosphingolipids and insulin resistance

    NARCIS (Netherlands)

    M. Langeveld; J.F.M.G. Aerts

    2009-01-01

    Obesity is associated with an increased risk for insulin resistance, a state characterized by impaired responsiveness of liver, muscle and adipose tissue to insulin. One class of lipids involved in the development of insulin resistance are the (glyco)sphingolipids. Ceramide, the most simple sphingol

  5. Regicide and Resistance

    DEFF Research Database (Denmark)

    Flohr, Mikkel

    2016-01-01

    This article examines the role of resistance in Michel Foucault’s political thought. The article recovers this otherwise obscured aspect of Foucault’s thought through a systematic analysis of his theoretical regicide and consequent reconceptualization of power, agency and resistance. It is argued...

  6. Resistance, Reactance, and Consultation.

    Science.gov (United States)

    Hughes, Jan N.; Falk, Robert S.

    1981-01-01

    Presents a review of techniques for dealing with consultee resistance. Suggests the social psychological theory of reactance is a useful conceptual framework for considering resistance in consultation. Discusses examples of its application, variables that predict the likely effectiveness of a reactance utilization intervention, and ethical issues.…

  7. Drug resistance in malaria

    Directory of Open Access Journals (Sweden)

    S C Parija

    2011-01-01

    Full Text Available Antimalarial chemotherapy is an important component of all malaria control programmes throughout the world. This is especially so in light of the fact that there are no antimalarial vaccines which are available for clinical use at present. Emergence and spread of malaria parasites which are resistant to many of the available antimalarials today is, therefore, a major cause for concern. Till date, resistance to all groups of antimalarials excluding artemisinin has been reported. In recent years, in vitro resistance to even artemisinin has been described. While resistance to antibacterial agents has come to prominence as a clinical problem in recent years, antiparasitic resistance in general and antimalarial resistance in particular has not received much attention, especially in the Indian scenario. The present review deals with commonly used antimalarial drugs and the mechanisms of resistance to them. Various methods of detecting antimalarial resistance and avoiding the same have also been dealt with. Newer parasite targets which can be used in developing newer antimalarial agents and antimalarials obtained from plants have also been mentioned.

  8. [Genetics and disease resistance].

    Science.gov (United States)

    Reiner, Gerald

    2008-07-01

    Genetic components of disease resistance have been described in most of important diseases in human as well as in laboratory and livestock animals. However the basic mechanisms have been established in a few examples only. The reasons herefore are the mostly polygenic inheritance of disease resistance traits, the missing of suitable animal models and the dominance of environmental effects like infection pressure, immune status, and stressors, limiting the view on responsible gene variants. Ethical and practical aspects may further hinder research on disease resistance in certain species. Livestock animals play a crucial role in disease resistance research, because of distinct genetic diversity within and between breeds, because of an often distinct metabolic congruency with humans, and aiming towards the improvement of hygiene and economy of production and animal welfare. The following sections will review disease resistance in livestock animals and their practical implications, completed by examples of our own research activities.

  9. Biological Threats Detection Technologies

    International Nuclear Information System (INIS)

    Among many decisive factors, which can have the influence on the possibility of decreases the results of use biological agents should be mentioned obligatory: rapid detection and identification of biological factor used, the proper preventive treatment and the medical management. The aims of identification: to identify the factor used, to estimate the area of contamination, to evaluate the possible countermeasure efforts (antibiotics, disinfectants) and to assess the effectiveness of the decontamination efforts (decontamination of the persons, equipment, buildings, environment etc.). The objects of identification are: bacteria and bacteria's spores, viruses, toxins and genetically modified factors. The present technologies are divided into: based on PCR techniques (ABI PRISM, APSIS, BIOVERIS, RAPID), immuno (BADD, RAMP, SMART) PCR and immuno techniques (APDS, LUMINEX) and others (BDS2, LUNASCAN, MALDI). The selected technologies assigned to field conditions, mobile and stationary laboratories will be presented.(author)

  10. Introduction to radiation biology

    International Nuclear Information System (INIS)

    This book is arranged in a logical sequence, starting from radiation physics and radiation chemistry, followed by molecular, subcellular and cellular effects and going on to the level of organism. Topics covered include applied radiobiology like modifiers of radiosensitivity, predictive assay, health physics, human genetics and radiopharmaceuticals. The topics covered are : 1. Radiation Physics, 2. Detection and Measurement of Radiation, 3. Radiation Chemistry, 4. DNA Damage and Repair, 5. Chromosomal Aberrations and Gene Mutations, 6. Cellular Radiobiology 7. Acute Radiation Effects, 8. Delayed Effects of Radiation, 9. Biological Basis of Radiotherapy, 10. Chemical Modifiers of Radiosensitivity, 11. Hyperthermia, 12. High LET Radiations in Cancer, Therapy, 13. Predictive Assays, 14. Radiation Effects on Embryos, 15. Human Radiation Genetics, 16. Radiolabelled Compounds in Biology and Medicine and 17. Radiological Health

  11. Radiation biology for environment

    International Nuclear Information System (INIS)

    Environmental pollution problems such as the green-house effect by increase of CO2, acid rain caused by flue gases, and contamination of chemicals and pesticides in foods and water, have become serious in the world with the rapid development of industry and agriculture. To solve some of these problems, radiation treatment has being applied for the removal of the contaminants from flue gases and waste water from industrial plants. On the other hand, the contribution of radiation biology for these environmental pollution problems is not direct but it has contributed indirectly in many fields. This paper describes the contributions of radiation biology for environment in the following two topics: 1) control of insects and microorganisms, and 2) application of radiation for agricultural wastes

  12. Traceability of biologicals

    DEFF Research Database (Denmark)

    Vermeer, Niels S; Spierings, Irina; Mantel-Teeuwisse, Aukje K;

    2015-01-01

    . Efforts to improve the traceability should, in the short term, be focused toward encouraging health professionals and patients to systematically record and report detailed exposure information. Long-term solutions lie in expanding the accessibility to, and increasing the electronic exchange of exposure......INTRODUCTION: Traceability is important in the postmarketing surveillance of biologicals, since changes in the manufacturing process may give rise to product- or batch-specific risks. With the expected expansion of the biosimilar market, there have been concerns about the ability to trace...... individual products within pharmacovigilance databases. AREAS COVERED: The authors discuss the present challenges in the traceability of biologicals in relation to pharmacovigilance, by exploring the processes involved in ensuring traceability. They explore both the existing systems that are in place...

  13. Biological scaling and physics

    Indian Academy of Sciences (India)

    A R P Rau

    2002-09-01

    Kleiber’s law in biology states that the specific metabolic rate (metabolic rate per unit mass) scales as -1/4 in terms of the mass of the organism. A long-standing puzzle is the (- 1/4) power in place of the usual expectation of (- 1/3) based on the surface to volume ratio in three-dimensions. While recent papers by physicists have focused exclusively on geometry in attempting to explain the puzzle, we consider here a specific law of physics that governs fluid flow to show how the (- 1/4) power arises under certain conditions. More generally, such a line of approach that identifies a specific physical law as involved and then examines the implications of a power law may illuminate better the role of physics in biology.

  14. Quantum physics meets biology.

    Science.gov (United States)

    Arndt, Markus; Juffmann, Thomas; Vedral, Vlatko

    2009-12-01

    Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the past decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world-view of quantum coherences, entanglement, and other nonclassical effects, has been heading toward systems of increasing complexity. The present perspective article shall serve as a "pedestrian guide" to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future "quantum biology," its current status, recent experimental progress, and also the restrictions that nature imposes on bold extrapolations of quantum theory to macroscopic phenomena.

  15. Biological scaling and physics.

    Science.gov (United States)

    Rau, A R P

    2002-09-01

    Kleiber's law in biology states that the specific metabolic rate (metabolic rate per unit mass) scales as M- 1/4 in terms of the mass M of the organism. A long-standing puzzle is the (- 1/4) power in place of the usual expectation of (- 1/3) based on the surface to volume ratio in three-dimensions. While recent papers by physicists have focused exclusively on geometry in attempting to explain the puzzle, we consider here a specific law of physics that governs fluid flow to show how the (- 1/4) power arises under certain conditions. More generally, such a line of approach that identifies a specific physical law as involved and then examines the implications of a power law may illuminate better the role of physics in biology.

  16. Topology in Molecular Biology

    CERN Document Server

    Monastyrsky, Michail Ilych

    2007-01-01

    The book presents a class of new results in molecular biology for which topological methods and ideas are important. These include: the large-scale conformation properties of DNA; computational methods (Monte Carlo) allowing the simulation of large-scale properties of DNA; the tangle model of DNA recombination and other applications of Knot theory; dynamics of supercoiled DNA and biocatalitic properties of DNA; the structure of proteins; and other very recent problems in molecular biology. The text also provides a short course of modern topology intended for the broad audience of biologists and physicists. The authors are renowned specialists in their fields and some of the new results presented here are documented for the first time in monographic form.

  17. Lagrangians for biological models

    CERN Document Server

    Nucci, M C

    2011-01-01

    We show that a method presented in [S.L. Trubatch and A. Franco, Canonical Procedures for Population Dynamics, J. Theor. Biol. 48 (1974), 299-324] and later in [G.H. Paine, The development of Lagrangians for biological models, Bull. Math. Biol. 44 (1982) 749-760] for finding Lagrangians of classic models in biology, is actually based on finding the Jacobi Last Multiplier of such models. Using known properties of Jacobi Last Multiplier we show how to obtain linear Lagrangians of those first-order systems and nonlinear Lagrangian of the corresponding single second-order equations that can be derived from them, even in the case where those authors failed such as the host-parasite model.

  18. Heritability and biological explanation.

    Science.gov (United States)

    Turkheimer, E

    1998-10-01

    Modern neuroscientific and genetic technologies have provoked intense disagreement between scientists who envision a future in which biogenetic theories will enrich or even replace psychological theories, and others who consider biogenetic theories exaggerated, dehumanizing, and dangerous. Both sides of the debate about the role of genes and brains in the genesis of human behavior have missed an important point: All human behavior that varies among individuals is partially heritable and correlated with measurable aspects of brains, but the very ubiquity of these findings makes them a poor basis for reformulating scientists' conceptions of human behavior. Materialism requires psychological processes to be physically instantiated, but more crucial for psychology is the occasional empirical discovery of behavioral phenomena that are specific manifestations of low-level biological variables. Heritability and psychobiological association cannot be the basis for establishing whether behavior is genetic or biological, because to do so leads only to the banal tautology that all behavior is ultimately based in the genotype and brain.

  19. Male mating biology

    OpenAIRE

    Howell Paul I; Knols Bart GJ

    2009-01-01

    Abstract Before sterile mass-reared mosquitoes are released in an attempt to control local populations, many facets of male mating biology need to be elucidated. Large knowledge gaps exist in how both sexes meet in space and time, the correlation of male size and mating success and in which arenas matings are successful. Previous failures in mosquito sterile insect technique (SIT) projects have been linked to poor knowledge of local mating behaviours or the selection of deleterious phenotypes...

  20. Dominating biological networks.

    Directory of Open Access Journals (Sweden)

    Tijana Milenković

    Full Text Available Proteins are essential macromolecules of life that carry out most cellular processes. Since proteins aggregate to perform function, and since protein-protein interaction (PPI networks model these aggregations, one would expect to uncover new biology from PPI network topology. Hence, using PPI networks to predict protein function and role of protein pathways in disease has received attention. A debate remains open about whether network properties of "biologically central (BC" genes (i.e., their protein products, such as those involved in aging, cancer, infectious diseases, or signaling and drug-targeted pathways, exhibit some topological centrality compared to the rest of the proteins in the human PPI network.To help resolve this debate, we design new network-based approaches and apply them to get new insight into biological function and disease. We hypothesize that BC genes have a topologically central (TC role in the human PPI network. We propose two different concepts of topological centrality. We design a new centrality measure to capture complex wirings of proteins in the network that identifies as TC those proteins that reside in dense extended network neighborhoods. Also, we use the notion of domination and find dominating sets (DSs in the PPI network, i.e., sets of proteins such that every protein is either in the DS or is a neighbor of the DS. Clearly, a DS has a TC role, as it enables efficient communication between different network parts. We find statistically significant enrichment in BC genes of TC nodes and outperform the existing methods indicating that genes involved in key biological processes occupy topologically complex and dense regions of the network and correspond to its "spine" that connects all other network parts and can thus pass cellular signals efficiently throughout the network. To our knowledge, this is the first study that explores domination in the context of PPI networks.

  1. Integrative radiation systems biology.

    Science.gov (United States)

    Unger, Kristian

    2014-01-01

    Maximisation of the ratio of normal tissue preservation and tumour cell reduction is the main concept of radiotherapy alone or combined with chemo-, immuno- or biologically targeted therapy. The foremost parameter influencing this ratio is radiation sensitivity and its modulation towards a more efficient killing of tumour cells and a better preservation of normal tissue at the same time is the overall aim of modern therapy schemas. Nevertheless, this requires a deep understanding of the molecular mechanisms of radiation sensitivity in order to identify its key players as potential therapeutic targets. Moreover, the success of conventional approaches that tried to statistically associate altered radiation sensitivity with any molecular phenotype such as gene expression proofed to be somewhat limited since the number of clinically used targets is rather sparse. However, currently a paradigm shift is taking place from pure frequentistic association analysis to the rather holistic systems biology approach that seeks to mathematically model the system to be investigated and to allow the prediction of an altered phenotype as the function of one single or a signature of biomarkers. Integrative systems biology also considers the data from different molecular levels such as the genome, transcriptome or proteome in order to partially or fully comprehend the causal chain of molecular mechanisms. An example for the application of this concept currently carried out at the Clinical Cooperation Group "Personalized Radiotherapy in Head and Neck Cancer" of the Helmholtz-Zentrum München and the LMU Munich is described. This review article strives for providing a compact overview on the state of the art of systems biology, its actual challenges, potential applications, chances and limitations in radiation oncology research working towards improved personalised therapy concepts using this relatively new methodology. PMID:24411063

  2. [Biological etiologies of transsexualism].

    Science.gov (United States)

    Butty, Anne-Virginie; Bianchi-Demicheli, Francesco

    2016-03-16

    Transsexualism or gender dysphoria is a disorder of sexual identity of unknown etiology. At the biological level, one assumes atypical brain development during certain periods of its formation (genesis) notably during embryogenesis, as a result of altered hormonal influence and a particular genetic polymorphism. This article summarizes the research conducted to date in these three areas only, excluding psycho-social and environmental factors. PMID:27149713

  3. Integrative radiation systems biology

    International Nuclear Information System (INIS)

    Maximisation of the ratio of normal tissue preservation and tumour cell reduction is the main concept of radiotherapy alone or combined with chemo-, immuno- or biologically targeted therapy. The foremost parameter influencing this ratio is radiation sensitivity and its modulation towards a more efficient killing of tumour cells and a better preservation of normal tissue at the same time is the overall aim of modern therapy schemas. Nevertheless, this requires a deep understanding of the molecular mechanisms of radiation sensitivity in order to identify its key players as potential therapeutic targets. Moreover, the success of conventional approaches that tried to statistically associate altered radiation sensitivity with any molecular phenotype such as gene expression proofed to be somewhat limited since the number of clinically used targets is rather sparse. However, currently a paradigm shift is taking place from pure frequentistic association analysis to the rather holistic systems biology approach that seeks to mathematically model the system to be investigated and to allow the prediction of an altered phenotype as the function of one single or a signature of biomarkers. Integrative systems biology also considers the data from different molecular levels such as the genome, transcriptome or proteome in order to partially or fully comprehend the causal chain of molecular mechanisms. An example for the application of this concept currently carried out at the Clinical Cooperation Group “Personalized Radiotherapy in Head and Neck Cancer” of the Helmholtz-Zentrum München and the LMU Munich is described. This review article strives for providing a compact overview on the state of the art of systems biology, its actual challenges, potential applications, chances and limitations in radiation oncology research working towards improved personalised therapy concepts using this relatively new methodology

  4. Biology of infantile hemangioma.

    Science.gov (United States)

    Itinteang, Tinte; Withers, Aaron H J; Davis, Paul F; Tan, Swee T

    2014-01-01

    Infantile hemangioma (IH), the most common tumor of infancy, is characterized by an initial proliferation during infancy followed by spontaneous involution over the next 5-10 years, often leaving a fibro-fatty residuum. IH is traditionally considered a tumor of the microvasculature. However, recent data show the critical role of stem cells in the biology of IH with emerging evidence suggesting an embryonic developmental anomaly due to aberrant proliferation and differentiation of a hemogenic endothelium with a neural crest phenotype that possesses the capacity for endothelial, hematopoietic, mesenchymal, and neuronal differentiation. Current evidence suggests a putative placental chorionic mesenchymal core cell embolic origin of IH during the first trimester. This review outlines the emerging role of stem cells and their interplay with the cytokine niche that promotes a post-natal environment conducive for vasculogenesis involving VEGFR-2 and its ligand VEGF-A and the IGF-2 ligand in promoting cellular proliferation, and the TRAIL-OPG anti-apoptotic pathway in preventing cellular apoptosis in IH. The discovery of the role of the renin-angiotensin system in the biology of IH provides a plausible explanation for the programed biologic behavior and the β-blocker-induced accelerated involution of this enigmatic condition. This crucially involves the vasoactive peptide, angiotensin II, that promotes cellular proliferation in IH predominantly via its action on the ATIIR2 isoform. The role of the RAS in the biology of IH is further supported by the effect of captopril, an ACE inhibitor, in inducing accelerated involution of IH. The discovery of the critical role of RAS in IH represents a novel and fascinating paradigm shift in the understanding of human development, IH, and other tumors in general. PMID:25593962

  5. Biology of Infantile Hemangioma

    OpenAIRE

    Itinteang, Tinte; Withers, Aaron H. J.; Davis, Paul F.; Tan, Swee T.

    2014-01-01

    Infantile hemangioma (IH), the most common tumor of infancy, is characterized by an initial proliferation during infancy followed by spontaneous involution over the next 5–10 years, often leaving a fibro-fatty residuum. IH is traditionally considered a tumor of the microvasculature. However, recent data show the critical role of stem cells in the biology of IH with emerging evidence suggesting an embryonic developmental anomaly due to aberrant proliferation and differentiation of a hemogenic ...

  6. Biological Correlates of Empathy

    Directory of Open Access Journals (Sweden)

    E. Timucin Oral

    2010-04-01

    Full Text Available Empathy can be defined as the capacity to know emotionally what another is experiencing from within the frame of reference of that other person and the capacity to sample the feelings of another or it can be metaphorized as to put oneself in another’s shoes. Although the concept of empathy was firstly described in psychological theories, researches studying the biological correlates of psychological theories have been increasing recently. Not suprisingly, dinamically oriented psychotherapists Freud, Kohut, Basch and Fenichel had suggested theories about the biological correlates of empathy concept and established the basis of this modality decades ago. Some other theorists emphasized the importance of empathy in the early years of lifetime regarding mother-child attachment in terms of developmental psychology and investigated its role in explanation of psychopathology. The data coming from some of the recent brain imaging and animal model studies also seem to support these theories. Although increased activity in different brain regions was shown in many of the brain imaging studies, the role of cingulate cortex for understanding mother-child relationship was constantly emphasized in nearly all of the studies. In addition to these studies, a group of Italian scientists has defined a group of neurons as “mirror neurons” in their studies observing rhesus macaque monkeys. Later, they also defined mirror neurons in human studies, and suggested them as “empathy neurons”. After the discovery of mirror neurons, the hopes of finding the missing part of the puzzle for understanding the biological correlates of empathy raised again. Although the roles of different biological parameters such as skin conductance and pupil diameter for defining empathy have not been certain yet, they are going to give us the opportunity to revise the inconsistent basis of structural validity in psychiatry and to stabilize descriptive validity. In this review, the

  7. Biological Rhythms and Preeclampsia

    OpenAIRE

    Ditisheim, Agnès J.; Dibner, Charna; Philippe, Jacques; Pechère-Bertschi, Antoinette

    2013-01-01

    The impact of impaired circadian rhythm on health has been widely studied in shift workers and trans-meridian travelers. A part from its correlation with sleep and mood disorders, biological rhythm impairment is a recognized risk factor for cardiovascular diseases and breast cancer. Preeclampsia is a major public health issue, associated with a significant maternal and fetal morbidity and mortality worldwide. While the risks factors for this condition such as obesity, diabetes, pre-existing h...

  8. Lung Stem cell biology

    OpenAIRE

    Ardhanareeswaran, Karthikeyan; Mirotsou, Maria

    2013-01-01

    Over the past few years new insights have been added to the study of stem cells in the adult lung. The exploration of the endogenous lung progenitors as well as the study of exogenously delivered stem cell populations holds promise for advancing our understanding of the biology of lung repair mechanisms. Moreover, it opens new possibilities for the use of stem cell therapy for the development of regenerative medicine approaches for the treatment of lung disease. Here, we discuss the main type...

  9. Elements in biological AMS

    International Nuclear Information System (INIS)

    AMS (Accelerator Mass Spectrometry) provides high detection sensitivity for isotopes whose half-lives are between 10 years and 100 million years. 14C is the most developed of such isotopes and is used in tracing natural and anthropogenic organic compounds in the Earth's biosphere. Thirty-three elements in the main periodic table and 17 lanthanides or actinides have long lived isotopes, providing potential tracers for research in elemental biochemistry. Overlap of biologically interesting heavy elements and possible AMS tracers is discussed

  10. Stability and fitness costs associated with etoxazole resistance in Tetranychus urticae (Acari: Tetranychidae).

    Science.gov (United States)

    Stocco, Rafael Sorrentino Minazzi; Sato, Mário Eidi; Santos, Taiana Lumi

    2016-08-01

    The two-spotted spider mite, Tetranychus urticae Koch, is one of the most important pests on a wide range of crops worldwide. Studies on stability of resistance and possible fitness costs associated with etoxazole resistance were carried out in T. urticae to provide basic information necessary to define effective acaricide resistance management strategies for this pest. Selection for resistance to etoxazole was performed in a population of T. urticae collected from a commercial rose field, in Holambra County, in the State of São Paulo, Brazil. After five rounds of selection for resistance, the resistance ratio (R/S) at the LC50 reached 8739 fold value in comparison with a susceptible strain (Brazabrantes S Strain). The stability of etoxazole resistance was studied under laboratory conditions, using a population with initial frequency of 75 % of resistant mites. The frequencies of etoxazole resistance were evaluated monthly for a period of 13 months. The frequency of etoxazole resistance decreased from 75 to 37 % in this period. Comparison of biological traits between resistant and susceptible strains indicated the presence of fitness costs associated with etoxazole resistance. The resistant strain showed lower fecundity and a higher proportion of males in the population. The figures for net reproductive rate (R 0), intrinsic rate of natural increase (r m) and finite rate of increase (λ) were higher in the susceptible strain. The instability of etoxazole resistance is a favorable aspect for the acaricide resistance management in the spider mite. PMID:27222145

  11. Neutrons in biology

    International Nuclear Information System (INIS)

    The start of JRR-3M in 1990 was a great epoch to the neutron scattering research in Japan. Abundant neutron beam generated by the JRR-3M made it possible to widen the research field of neutron scattering in Japan. In the early days of neutron scattering, biological materials were too difficult object to be studied by neutrons not only because of their complexity but also because of the strong incoherent scattering by hydrogen. However, the remarkable development of the recent neutron scattering and its related sciences, as well as the availability of higher flux, has made the biological materials one of the most attractive subjects to be studied by neutrons. In early September 1992, an intensive workshop titled 'Neutrons in Biology' was held in Hitachi City by making use of the opportunity of the 4th International Conference on Biophysics and Synchrotron Radiation (BSR92) held in Tsukuba. The workshop was organized by volunteers who are eager to develop the researches in this field in Japan. Numbers of outstanding neutron scattering biologists from U.S., Europe and Asian countries met together and enthusiastic discussions were held all day long. The editors believe that the presentations at the workshop were so invaluable that it is absolutely adequate to put them on record as an issue of JAERI-M and to make them available for scientists to refer to in order to further promote the research in the future. (author)

  12. Biological heart valves.

    Science.gov (United States)

    Ciubotaru, Anatol; Cebotari, Serghei; Tudorache, Igor; Beckmann, Erik; Hilfiker, Andres; Haverich, Axel

    2013-10-01

    Cardiac valvular pathologies are often caused by rheumatic fever in young adults, atherosclerosis in elderly patients, or by congenital malformation of the heart in children, in effect affecting almost all population ages. Almost 300,000 heart valve operations are performed worldwide annually. Tissue valve prostheses have certain advantages over mechanical valves such as biocompatibility, more physiological hemodynamics, and no need for life-long systemic anticoagulation. However, the major disadvantage of biological valves is related to their durability. Nevertheless, during the last decade, the number of patients undergoing biological, rather than mechanical, valve replacement has increased from half to more than three-quarters for biological implants. Continuous improvement in valve fabrication includes development of new models and shapes, novel methods of tissue treatment, and preservation and implantation techniques. These efforts are focused not only on the improvement of morbidity and mortality of the patients but also on the improvement of their quality of life. Heart valve tissue engineering aims to provide durable, "autologous" valve prostheses. These valves demonstrate adaptive growth, which may avoid the need of repeated operations in growing patients.

  13. Synthetic biology: advancing biological frontiers by building synthetic systems

    OpenAIRE

    Chen, Yvonne Yu-Hsuan; Galloway, Kate E.; Smolke, Christina D.

    2012-01-01

    Advances in synthetic biology are contributing to diverse research areas, from basic biology to biomanufacturing and disease therapy. We discuss the theoretical foundation, applications, and potential of this emerging field.

  14. Marine molecular biology: An emerging field of biological sciences

    Digital Repository Service at National Institute of Oceanography (India)

    Thakur, N.L.; Jain, R.; Natalio, F.; Hamer, B.; Thakur, A.N.; Muller, W.E.G.

    the sustainable exploration of marine life for human health and welfare, through the cooperation between scientists working in marine biology, molecular biology, microbiology and chemistry disciplines. Several success stories of the applications of molecular...

  15. Update on antifungal drug resistance mechanisms of Aspergillus fumigatus.

    Science.gov (United States)

    Chamilos, G; Kontoyiannis, D P

    2005-12-01

    Although the arsenal of agents with anti-Aspergillus activity has expanded over the last decade, mortality due to invasive aspergillosis (IA) remains unacceptably high. Aspergillus fumigatus still accounts for the majority of cases of IA; however less susceptible to antifungals non-fumigatus aspergilli began to emerge. Antifungal drug resistance of Aspergillus might partially account for treatment failures. Recent advances in our understanding of mechanisms of antifungal drug action in Aspergillus, along with the standardization of in vitro susceptibility testing methods, has brought resistance testing to the forefront of clinical mycology. In addition, molecular biology has started to shed light on the mechanisms of resistance of A. fumigatus to azoles and the echinocandins, while genome-based assays show promise for high-throughput screening for genotypic antifungal resistance. Several problems remain, however, in the study of this complex area. Large multicenter clinical studies--point prevalence or longitudinal--to capture the incidence and prevalence of antifungal resistance in A. fumigatus isolates are lacking. Correlation of in vitro susceptibility with clinical outcome and susceptibility breakpoints has not been established. In addition, the issue of cross-resistance between the newer triazoles is of concern. Furthermore, in vitro resistance testing for polyenes and echinocandins is difficult, and their mechanisms of resistance are largely unknown. This review examines challenges in the diagnosis, epidemiology, and mechanisms of antifungal drug resistance in A. fumigatus. PMID:16488654

  16. Detection of antibiotic resistance in probiotics of dietary supplements

    KAUST Repository

    Wong, Aloysius Tze

    2015-09-14

    Background Probiotics are live microorganisms that confer nutrition- and health-promoting benefits if consumed in adequate amounts. Concomitant with the demand for natural approaches to maintaining health is an increase in inclusion of probiotics in food and health products. Since probiotic bacteria act as reservoir for antibiotic resistant determinants, the transfer of these genes to pathogens sharing the same intestinal habitat is thus conceivable considering the fact that dietary supplements contain high amounts of often heterogeneous populations of probiotics. Such events can confer pathogens protection against commonly-used drugs. Despite numerous reports of antibiotic resistant probiotics in food and biological sources, the antibiogram of probiotics from dietary supplements remained elusive. Findings Here, we screened five commercially available dietary supplements for resistance towards antibiotics of different classes. Probiotics of all batches of products were resistant towards vancomycin while batch-dependent resistance towards streptomycin, aztreonam, gentamycin and/or ciprofloxacin antibiotics was detected for probiotics of brands Bi and Bn, Bg, and L. Isolates of brand Cn was also resistant towards gentamycin, streptomycin and ciprofloxacin antibiotics. Additionally, we also report a discrepancy between the enumerated viable bacteria amounts and the claims of the manufacturers. Conclusions This short report has highlighted the present of antibiotic resistance in probiotic bacteria from dietary supplements and therefore serves as a platform for further screenings and for in-depth characterization of the resistant determinants and the molecular machinery that confers the resistance.

  17. Antibiotic Resistance Pattern of Gram-Negative Bacteria in Gorgan

    Directory of Open Access Journals (Sweden)

    Golsha, R. (MD

    2014-06-01

    Full Text Available Background and Objective: The excessive use of broad-spectrum antibiotics will lead to drug resistance of microorganism and specially nosocomial organisms. Because of high incidence of antibiotic resistance in hospitals, we aimed to study antibiotic resistance to gram negative bacteria. Material and Methods: This cross-sectional study was conducted on the data of biological samples (2006-2008, with positive culture result. Using antibiogram, microbial resistance to isolated microorganism was determined, and after culturing the samples, bacteria were identified by using differential media and antiserum. Then, antibiotic resistance was performed by disk diffusion. Results: The most common gram-negative microorganism obtained from all cultures was E.coli with the lowest drug resistance to Nitrofurantoin. Conclusion: Based on the results, antimicrobial resistance pattern is not the same in different places and furthermore it is ever changing. Therefore, further research is needed to be done to have an accurate pattern of antibiotic resistance to provide effective treatment regimens. Key words: Antibiotic Resistance; Disk Diffusion; Gram Negative Bacteria; Gorgan

  18. Synthetic biology: Understanding biological design from synthetic circuits

    OpenAIRE

    Mukherji, Shankar; van Oudenaarden, Alexander

    2009-01-01

    An important aim of synthetic biology is to uncover the design principles of natural biological systems through the rational design of gene and protein circuits. Here, we highlight how the process of engineering biological systems — from synthetic promoters to the control of cell–cell interactions — has contributed to our understanding of how endogenous systems are put together and function. Synthetic biological devices allow us to grasp intuitively the ranges of behaviour generated by simple...

  19. 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...

  20. Bridging the gap between systems biology and synthetic biology

    OpenAIRE

    Liu, Di; Hoynes-O’Connor, Allison; Zhang, Fuzhong

    2013-01-01

    Systems biology is an inter-disciplinary science that studies the complex interactions and the collective behavior of a cell or an organism. Synthetic biology, as a technological subject, combines biological science and engineering, allowing the design and manipulation of a system for certain applications. Both systems and synthetic biology have played important roles in the recent development of microbial platforms for energy, materials, and environmental applications. More importantly, syst...

  1. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... FDA Submit search Popular Content Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary ... by Product Area Product Areas back Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary ...

  2. Biological surface science

    Science.gov (United States)

    Kasemo, Bengt

    2002-03-01

    Biological surface science (BioSS), as defined here is the broad interdisciplinary area where properties and processes at interfaces between synthetic materials and biological environments are investigated and biofunctional surfaces are fabricated. Six examples are used to introduce and discuss the subject: Medical implants in the human body, biosensors and biochips for diagnostics, tissue engineering, bioelectronics, artificial photosynthesis, and biomimetic materials. They are areas of varying maturity, together constituting a strong driving force for the current rapid development of BioSS. The second driving force is the purely scientific challenges and opportunities to explore the mutual interaction between biological components and surfaces. Model systems range from the unique water structures at solid surfaces and water shells around proteins and biomembranes, via amino and nucleic acids, proteins, DNA, phospholipid membranes, to cells and living tissue at surfaces. At one end of the spectrum the scientific challenge is to map out the structures, bonding, dynamics and kinetics of biomolecules at surfaces in a similar way as has been done for simple molecules during the past three decades in surface science. At the other end of the complexity spectrum one addresses how biofunctional surfaces participate in and can be designed to constructively participate in the total communication system of cells and tissue. Biofunctional surfaces call for advanced design and preparation in order to match the sophisticated (bio) recognition ability of biological systems. Specifically this requires combined topographic, chemical and visco-elastic patterns on surfaces to match proteins at the nm scale and cells at the micrometer scale. Essentially all methods of surface science are useful. High-resolution (e.g. scanning probe) microscopies, spatially resolved and high sensitivity, non-invasive optical spectroscopies, self-organizing monolayers, and nano- and microfabrication

  3. Methicillin resistance & inducible clindamycin resistance in Staphylococcus aureus

    OpenAIRE

    Soumyadeep Ghosh; Mandira Banerjee

    2016-01-01

    Background & objectives: Methicillin resistant Staphylococcus aureus (MRSA) isolates with inducible clindamycin resistance (iCR) are resistant to erythromycin and sensitive to clindamycin on routine testing and inducible clindamycin resistance can only be identified by D-test. This study was aimed to detect methicillin resistance and iCR among S. aureus isolates, effectiveness of some commonly used antibiotics and correlation between methicillin resistance and iCR. Methods: The present cro...

  4. Ecological aspects of the multidrug resistance to chemotherapy agents

    OpenAIRE

    Volkova Tatyana; Bagina Ulyana

    2012-01-01

    This paper presents generalized and analyzed literature data concerning the main mechanisms of the development of multidrug resistance (MDR) produced by tumour cells to chemotherapeutic agents. The conclusion is made about the biological role of acquired MDR phenotype for the tumour cell population.

  5. The biology of hair diversity.

    Science.gov (United States)

    Westgate, Gillian E; Botchkareva, Natalia V; Tobin, Desmond J

    2013-08-01

    Hair diversity, its style, colour, shape and growth pattern is one of our most defining characteristics. The natural versus temporary style is influenced by what happens to our hair during our lifetime, such as genetic hair loss, sudden hair shedding, greying and pathological hair loss in the various forms of alopecia because of genetics, illness or medication. Despite the size and global value of the hair care market, our knowledge of what controls the innate and within-lifetime characteristics of hair diversity remains poorly understood. In the last decade, drivers of knowledge have moved into the arena of genetics where hair traits are obvious and measurable and genetic polymorphisms are being found that raise valuable questions about the biology of hair growth. The recent discovery that the gene for trichohyalin contributes to hair shape comes as no surprise to the hair biologists who have believed for 100 years that hair shape is linked to the structure and function of the inner root sheath. Further conundrums awaiting elucidation include the polymorphisms in the androgen receptor (AR) described in male pattern alopecia whose location on the X chromosome places this genetic contributor into the female line. The genetics of female hair loss is less clear with polymorphisms in the AR not associated with female pattern hair loss. Lifestyle choices are also implicated in hair diversity. Greying, which also has a strong genetic component, is often suggested to have a lifestyle (stress) influence and hair follicle melanocytes show declining antioxidant protection with age and lowered resistance to stress. It is likely that hair research will undergo a renaissance on the back of the rising information from genetic studies as well as the latest contributions from the field of epigenetics.

  6. Linezolid Resistance in Staphylococci

    Directory of Open Access Journals (Sweden)

    Stefania Stefani

    2010-06-01

    Full Text Available Linezolid, the first oxazolidinone to be used clinically, is effective in the treatment of infections caused by various Gram-positive pathogens, including multidrug resistant enterococci and methicillin-resistant Staphylococus aureus. It has been used successfully for the treatment of patients with endocarditis and bacteraemia, osteomyelitis, joint infections and tuberculosis and it is often used for treatment of complicated infections when other therapies have failed. Linezolid resistance in Gram-positive cocci has been encountered clinically as well as in vitro, but it is still a rare phenomenon. The resistance to this antibiotic has been, until now, entirely associated with distinct nucleotide substitutions in domain V of the 23S rRNA genes. The number of mutated rRNA genes depends on the dose and duration of linezolid exposure and has been shown to influence the level of linezolid resistance. Mutations in associated ribosomal proteins also affect linezolid activity. A new phenicol and clindamycin resistance phenotype has recently been found to be caused by an RNA methyltransferase designated Cfr. This gene confers resistance to lincosamides, oxazolidinones, streptogramin A, phenicols and pleuromutilins, decrease the susceptibility of S. aureus to tylosin, to josamycin and spiramycin and thus differs from erm rRNA methylase genes. Research into new oxazolidinones with improved characteristics is ongoing. Data reported in patent applications demonstrated that some oxazolidinone derivatives, also with improved characteristics with respect to linezolid, are presently under study: at least three of them are in an advanced phase of development.

  7. Logical analysis of biological systems

    DEFF Research Database (Denmark)

    Mardare, Radu Iulian

    2005-01-01

    R. Mardare, Logical analysis of biological systems. Fundamenta Informaticae, N 64:271-285, 2005.......R. Mardare, Logical analysis of biological systems. Fundamenta Informaticae, N 64:271-285, 2005....

  8. Is Our Biology to Blame?

    Science.gov (United States)

    Schneider, Scott

    1977-01-01

    Brief analyses of three recent examples of biological determinism: sex roles, overpopulation, and sociobiology, are presented in this article. Also a brief discussion of biological determinism and education is presented. (MR)

  9. Biological treatment of Crohn's disease

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Bjerrum, Jacob Tveiten; Seidelin, Jakob Benedict;

    2012-01-01

    Introduction of biological agents for the treatment of Crohn's disease (CD) has led to a transformation of the treatment paradigm. Several biological compounds have been approved for patients with CD refractory to conventional treatment: infliximab, adalimumab and certolizumab pegol (and...

  10. American Institute of Biological Sciences

    Science.gov (United States)

    ... About | Newsroom | Contact Us The American Institute of Biological Sciences is the national scientific organization that promotes the ... Education Research AIBS Education is dedicated to improving biological science literacy at all levels of formal and informal ...

  11. Multidrug-resistant tuberculosis

    Directory of Open Access Journals (Sweden)

    McNerney Ruth

    2008-01-01

    Full Text Available Abstract Background With almost 9 million new cases each year, tuberculosis remains one of the most feared diseases on the planet. Led by the STOP-TB Partnership and WHO, recent efforts to combat the disease have made considerable progress in a number of countries. However, the emergence of mutated strains of Mycobacterium tuberculosis that are resistant to the major anti-tuberculosis drugs poses a deadly threat to control efforts. Multidrug-resistant tuberculosis (MDR-TB has been reported in all regions of the world. More recently, extensively drug resistant-tuberculosis (XDR-TB that is also resistant to second line drugs has emerged in a number of countries. To ensure that adequate resources are allocated to prevent the emergence and spread of drug resistance it is important to understand the scale of the problem. In this article we propose that current methods of describing the epidemiology of drug resistant tuberculosis are not adequate for this purpose and argue for the inclusion of population based statistics in global surveillance data. Discussion Whereas the prevalence of tuberculosis is presented as the proportion of individuals within a defined population having disease, the prevalence of drug resistant tuberculosis is usually presented as the proportion of tuberculosis cases exhibiting resistance to anti-tuberculosis drugs. Global surveillance activities have identified countries in Eastern Europe, the former Soviet Union and regions of China as having a high proportion of MDR-TB cases and international commentary has focused primarily on the urgent need to improve control in these settings. Other regions, such as sub-Saharan Africa have been observed as having a low proportion of drug resistant cases. However, if one considers the incidence of new tuberculosis cases with drug resistant disease in terms of the population then countries of sub-Saharan Africa have amongst the highest rates of transmitted MDR-TB in the world. We propose

  12. Fire resistant hydraulic fluids

    Energy Technology Data Exchange (ETDEWEB)

    Deakin, P. (Croda Application Chemicals Ltd. (UK). Mining Sales and Service)

    The use of fire resistant fluids is now widespread and in certain applications, namely underground, mandatory within the coal mining industry. However, safety is a paramount objective in all industries and within the author's company which supplies and services other industries such as metal forming and automotive construction, greater emphasis is being placed on the use of fire resistant hydraulic fluids. Their involvement with development, manufacture and application is continually expanding. This document describes the various fire resistant hydraulic fluids and why they are used in particular applications. 1 tab.

  13. Sustainable control of pea bacterial blight : approaches for durable genetic resistance and biocontrol by endophytic bacteria

    NARCIS (Netherlands)

    Elvira-Recuenco, M.

    2000-01-01

    Key-words: bacterial blight, biological control, biodiversity, endophytic bacteria, L-form, pea, PDRl retrotransposon, Pisum sativum, Pisum abyssinicum, Pseudomonas syringae pv. pisi, race specific resistance, race non-specific resistance, Spanish landraces.Pea bacterial blight (Pseudom

  14. [The corrosion resistance of aluminum and aluminum-based alloys studied in artificial model media].

    Science.gov (United States)

    Zhakhangirov, A Zh; Doĭnikov, A I; Aboev, V G; Iankovskaia, T A; Karamnova, V S; Sharipov, S M

    1991-01-01

    Samples of aluminum and its alloys, designed for orthodontic employment, were exposed to 4 media simulating the properties of biologic media. The corrosion resistance of the tested alloys was assessed from the degree of aluminum migration to simulation media solutions, which was measured by the neutron activation technique. Aluminum alloy with magnesium and titanium has shown the best corrosion resistance. PMID:1799002

  15. [Progress in researches on molecular markers of Plasmodium falciparum drug resistance].

    Science.gov (United States)

    Zhang, Mei-hua; Lu, Feng; Cao, Jun; Gao, Qi

    2015-06-01

    Effective chemotherapy is the mainstay of malaria control. However, it is undergoing the serious threat by resis- tance of falciparum malaria to antimalarial drugs. In recent years, with the development of molecular biology technology, molec- ular markers have been widely used to monitor antimalarial drug resistance. This paper reviews the researches on the common molecular markers related to Plasmodiumfalciparum drug resistance.

  16. Biology of Applied Digital Ecosystems

    OpenAIRE

    Briscoe, G.; Sadedin, S.; Paperin, G.

    2007-01-01

    A primary motivation for our research in Digital Ecosystems is the desire to exploit the self-organising properties of biological ecosystems. Ecosystems are thought to be robust, scalable architectures that can automatically solve complex, dynamic problems. However, the biological processes that contribute to these properties have not been made explicit in Digital Ecosystems research. Here, we discuss how biological properties contribute to the self-organising features of biological ecosystem...

  17. Logical impossibilities in biological networks

    Directory of Open Access Journals (Sweden)

    Monendra Grover

    2011-10-01

    Full Text Available Biological networks are complex and involve several kinds of molecules. For proper biological function it is important for these biomolecules to act at an individual level and act at the level of interaction of these molecules. In this paper some of the logical impossibilities that may arise in the biological networks and their possible solutions are discussed. It may be important to understand these paradoxes and their possible solutions in order to develop a holistic view of biological function.

  18. Attitude of teenagers towards biology

    OpenAIRE

    Lavtižar, Teja

    2016-01-01

    ROSE project is a comprehensive study in which students' attitudes towards Science and Technology affected by many factors have been examined. In our study, only some aspects have been focused due to a narrower field of biology which has been interested in, and the direction of the attitude between Biology to elementary school students has been checked. The purpose of the master's work has been to determine the attitude of the teenagers to Biology as science and Biology as a school subjec...

  19. Hydraulic resistance of biofilms

    KAUST Repository

    Dreszer, C.

    2013-02-01

    Biofilms may interfere with membrane performance in at least three ways: (i) increase of the transmembrane pressure drop, (ii) increase of feed channel (feed-concentrate) pressure drop, and (iii) increase of transmembrane passage. Given the relevance of biofouling, it is surprising how few data exist about the hydraulic resistance of biofilms that may affect the transmembrane pressure drop and membrane passage. In this study, biofilms were generated in a lab scale cross flow microfiltration system at two fluxes (20 and 100Lm-2h-1) and constant cross flow (0.1ms-1). As a nutrient source, acetate was added (1.0mgL-1 acetate C) besides a control without nutrient supply. A microfiltration (MF) membrane was chosen because the MF membrane resistance is very low compared to the expected biofilm resistance and, thus, biofilm resistance can be determined accurately. Transmembrane pressure drop was monitored. As biofilm parameters, thickness, total cell number, TOC, and extracellular polymeric substances (EPS) were determined, it was demonstrated that no internal membrane fouling occurred and that the fouling layer actually consisted of a grown biofilm and was not a filter cake of accumulated bacterial cells. At 20Lm-2h-1 flux with a nutrient dosage of 1mgL-1 acetate C, the resistance after 4 days reached a value of 6×1012m-1. At 100Lm-2h-1 flux under the same conditions, the resistance was 5×1013m-1. No correlation of biofilm resistance to biofilm thickness was found; Biofilms with similar thickness could have different resistance depending on the applied flux. The cell number in biofilms was between 4×107 and 5×108 cellscm-2. At this number, bacterial cells make up less than a half percent of the overall biofilm volume and therefore did not hamper the water flow through the biofilm significantly. A flux of 100Lm-2h-1 with nutrient supply caused higher cell numbers, more biomass, and higher biofilm resistance than a flux of 20Lm-2h-1. However, the biofilm thickness

  20. Multidrug resistance associated proteins in multidrug resistance

    Institute of Scientific and Technical Information of China (English)

    Kamlesh Sodani; Atish Patel; Rishil J. Kathawala; Zhe-Sheng Chen

    2012-01-01

    Multidrug resistance proteins (MRPs) are members of the C family of a group of proteins named ATP-binding cassette (ABC) transporters.These ABC transporters together form the largest branch of proteins within the human body.The MRP family comprises of 13 members,of which MRP1 to MRP9 are the major transporters indicated to cause multidrug resistance in tumor cells by extruding anticancer drugs out of the cell.They are mainly lipophilic anionic transporters and are reported to transport free or conjugates of glutathione (GSH),glucuronate,or sulphate.In addition,MRP1 to MRP3 can transport neutral organic drugs in free form in the presence of free GSH.Collectively,MRPs can transport drugs that differ structurally and mechanistically,including natural anticancer drugs,nucleoside analogs,antimetabolites,and tyrosine kinase inhibitors.Many of these MRPs transport physiologically important anions such as leukotriene C4,bilirubin glucuronide,and cyclic nucleotides.This review focuses mainly on the physiological functions,cellular resistance characteristics,and probable in vivo role of MRP1 to MRP9.

  1. Functions in Biological Kind Classification

    Science.gov (United States)

    Lombrozo, Tania; Rehder, Bob

    2012-01-01

    Biological traits that serve functions, such as a zebra's coloration (for camouflage) or a kangaroo's tail (for balance), seem to have a special role in conceptual representations for biological kinds. In five experiments, we investigate whether and why functional features are privileged in biological kind classification. Experiment 1…

  2. Semiconductor nanostructures in biological applications

    Energy Technology Data Exchange (ETDEWEB)

    Alexson, Dimitri [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Chen Hongfeng [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Cho, Michael [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Department of Physics, University of Illinois at Chicago, Chicago, IL 60607 (United States); Dutta, Mitra [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Department of Physics, University of Illinois at Chicago, Chicago, IL 60607 (United States); Li Yang [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Shi, Peng [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Raichura, Amit [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Ramadurai, Dinakar [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Parikh, Shaunak [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Stroscio, Michael A [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Department of Physics, University of Illinois at Chicago, Chicago, IL 60607 (United States); Vasudev, Milana [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States)

    2005-07-06

    Semiconductor nanostructures in biological applications are discussed. Results are presented on the use of colloidal semiconductor quantum dots both as biological tags and as structures that interact with and influence biomolecules. Results are presented on the use of semiconducting carbon nanotubes in biological applications. (topical review)

  3. Biological Computing Fundamentals and Futures

    CERN Document Server

    Akula, Balaji

    2009-01-01

    The fields of computing and biology have begun to cross paths in new ways. In this paper a review of the current research in biological computing is presented. Fundamental concepts are introduced and these foundational elements are explored to discuss the possibilities of a new computing paradigm. We assume the reader to possess a basic knowledge of Biology and Computer Science

  4. ECO-BIOLOGICAL SYSTEM MODELING

    Directory of Open Access Journals (Sweden)

    T. I. Burak

    2015-01-01

    Full Text Available The methodology for computer modeling of complex eco-biological models is presented in this paper. It is based on system approach of J. Forrester. Developed methodology is universal for complex ecological and biological systems. Modeling algorithm considers specialties of eco-biological systems and shows adequate and accurate results in practice. 

  5. Allometric Scaling in Biology

    Science.gov (United States)

    Banavar, Jayanth

    2009-03-01

    The unity of life is expressed not only in the universal basis of inheritance and energetics at the molecular level, but also in the pervasive scaling of traits with body size at the whole-organism level. More than 75 years ago, Kleiber and Brody and Proctor independently showed that the metabolic rates, B, of mammals and birds scale as the three-quarter power of their mass, M. Subsequent studies showed that most biological rates and times scale as M-1/4 and M^1/4 respectively, and that these so called quarter-power scaling relations hold for a variety of organisms, from unicellular prokaryotes and eukaryotes to trees and mammals. The wide applicability of Kleiber's law, across the 22 orders of magnitude of body mass from minute bacteria to giant whales and sequoias, raises the hope that there is some simple general explanation that underlies the incredible diversity of form and function. We will present a general theoretical framework for understanding the relationship between metabolic rate, B, and body mass, M. We show how the pervasive quarter-power biological scaling relations arise naturally from optimal directed resource supply systems. This framework robustly predicts that: 1) whole organism power and resource supply rate, B, scale as M^3/4; 2) most other rates, such as heart rate and maximal population growth rate scale as M-1/4; 3) most biological times, such as blood circulation time and lifespan, scale as M^1/4; and 4) the average velocity of flow through the network, v, such as the speed of blood and oxygen delivery, scales as M^1/12. Our framework is valid even when there is no underlying network. Our theory is applicable to unicellular organisms as well as to large animals and plants. This work was carried out in collaboration with Amos Maritan along with Jim Brown, John Damuth, Melanie Moses, Andrea Rinaldo, and Geoff West.

  6. Biology Reflective Assessment Curriculum

    Science.gov (United States)

    Bayley, Cheryl Ann

    Often students and educators view assessments as an obligation and finality for a unit. In the current climate of high-stakes testing and accountability, the balance of time, resources and emphasis on students' scores related to assessment have been slanted considerably toward the summative side. This tension between assessment for accountability and assessment to inform teaching strains instruction and educators' ability to use that information to design learning opportunities that help students develop deeper conceptual understanding. A substantive body of research indicates that formative and reflective assessment can significantly improve student learning. Biology Reflective Assessment Curriculum (BRAC) examines support provided for high school science students through assessment practices. This investigation incorporates the usage of reflective assessments as a guiding practice for differentiated instruction and student choice. Reflective assessment is a metacognitive strategy that promotes self-monitoring and evaluation. The goals of the curriculum are to promote self-efficacy and conceptual understanding in students learning biology through developing their metacognitive awareness. BRAC was implemented in a high school biology classroom. Data from assessments, metacognitive surveys, self-efficacy surveys, reflective journals, student work, a culminating task and field notes were used to evaluate the effectiveness of the curriculum. The results suggest that students who develop their metacognitive skills developed a deeper conceptual understanding and improved feelings of self-efficacy when they were engaged in a reflective assessment unit embedded with student choice. BRAC is a tool for teachers to use assessments to assist students in becoming metacognitive and to guide student choice in learning opportunities.

  7. The Promises of Biology and the Biology of Promises

    DEFF Research Database (Denmark)

    Lee, Jieun

    2015-01-01

    commitments with differently imagined futures. I argue that promises are constitutive of the stem cell biology, rather than being derivative of it. Since the biological concept of stem cells is predicated on the future that they promise, the biological life of stem cells is inextricably intertwined...... patients’ bodies in anticipation of materializing the promises of stem cell biology, they are produced as a new form of biovaluable. The promises of biology move beyond the closed circuit of scientific knowledge production, and proliferate in the speculative marketplaces of promises. Part II looks at how...... of technologized biology and biological time can appear promising with the backdrop of the imagined intransigence of social, political, and economic order in the Korean society....

  8. Biological Petri Nets

    CERN Document Server

    Wingender, E

    2011-01-01

    It was suggested some years ago that Petri nets might be well suited to modeling metabolic networks, overcoming some of the limitations encountered by the use of systems employing ODEs (ordinary differential equations). Much work has been done since then which confirms this and demonstrates the usefulness of this concept for systems biology. Petri net technology is not only intuitively understood by scientists trained in the life sciences, it also has a robust mathematical foundation and provides the required degree of flexibility. As a result it appears to be a very promising approach to mode

  9. Biology Attitude Scale

    OpenAIRE

    YEŞİLYURT, Selami; GÜL, Şeyda

    2009-01-01

    The aim of this study is to develop a scale determining secondary school stu- dent’s attitude towards biology. For this aim, at first, totally 92 scale items were prepared by reviewing relevant literature. 88 items in this scale were a five-point Likert type scale. 4 of 92 items consisted of demographic variables. The scale was applied to a sample of 109 students randomly selected from two secondary schools in Erzurum. At the end of this application, SPSS 12.0 Statistical Program was used to ...

  10. Programme Biology - Health protection

    International Nuclear Information System (INIS)

    The scientific results for 1975, of the five-year Biology-Health Protection programme adopted in 1971, are presented in two volumes. In volume one, Research in Radiation Protection are developed exclusively, including the following topics: measurement and interpretation of radiation (dosimetry); transfer of radioactive nuclides in the constituents of the environment; hereditary effects of radiation; short-term effects (acute irradiation syndrome and its treatment); long-term effects and toxicology of radioactive elements. In volume, two Research on applications in Agriculture and Medicine are developed. It includes: mutagenesis; soil-plant relations; radiation analysis; food conservation; cell culture; radioentomology. Research on applications in Medicine include: Nuclear Medicine and Neutron Dosimetry

  11. Biology of Nanobots

    Science.gov (United States)

    Duan, Wentao; Pavlick, Ryan; Sen, Ayusman

    2013-12-01

    One of the more interesting recent discoveries has been the ability to design nano/microbots which catalytically harness the chemical energy in their environment to move autonomously. Their potential applications include delivery of materials, self-assembly of superstructures, and roving sensors. One emergent area of research is the study of their collective behavior and how they emulate living systems. The aim of this chapter is to describe the "biology" of nanobots, summarizing the fundamentals physics behind their motion and how the bots interact with each other to initiate complex emergent behavior.

  12. Mathematics and biology

    International Nuclear Information System (INIS)

    In India and in so many other countries, the science students are generally separated into two main streams: one opting mathematical sciences, the other studying biological sciences. As a result, medicos and biologists have no adequate knowledge of mathematical sciences. It causes a great drawback to them in order to be perfect and updated in their profession, due to the tremendous application of mathematics in bio-sciences, now-a-days. The main aim of this article is to emphasize on the need of the time to produce the mathematico-biologists in abundance for the better service of mankind. (author)

  13. [Woman and race biology].

    Science.gov (United States)

    Hanson, H

    1993-01-01

    Early 20th century race biology takes a special interest in woman as part of the "intra-racial" project of bringing forth healthy and competitive individuals. But there are other motives as well for the race biologist to take an interest in woman. She is believed to develop fewer individual characteristics and is therefore a more typical representative of her race than man. The development level of the race is also presupposed to be discernible by the degree of "gender diformism": a race of higher standing would exhibit a greater difference between the sexes. The anthropologist, anatomist, gynaecologist--or whatever guise the race biologist may adopt-- will, in principle, stress that the relation between the sexes is not a matter of "more or less", but one of differences in kind. In reality, the "more-or-less of comparison is the very cornerstone of the issue. Quantitative differences, directly observed or obtained from statistics, are construed as signs of difference in kind. 18th century medical philosophy and sex-linked anthropology laid the theoretical foundation of the 19th century essentialist conception of woman, which is also that adopted by race biology. Eugenics of social Darwinist inspiration regarded prophylactic health care and social welfare programs with scepticism. A race biology founded on the man-woman dualism could sustain altogether different conclusions. An advanced culture calls for extensive division of labour. An extended childhood renders possible higher development but will also impose higher demands on woman. The protection of the female organism is thus an exigency for any people or race striving to survive and evolve. From society's care for the female organism health care for women and preventive maternity care will emerge. Race biology has been a preeminently German concern, as indicated by the selection of works taken to represent this perspective on woman: Bartels-Ploss' Das Weib, C.H. Stratz' Die Rassenschönheit des Weibes and

  14. [The biologization of ethics].

    Science.gov (United States)

    Moreno Lax, Alejandro

    2010-01-01

    Three ethics exist as a condition of possibility of any possible ethics, following a material and biological foundation. This content argument (not logical-formal) supposes a refutation of the naturalistic fallacy that the analytical philosophy attributes to Hume, in three areas of the ethical human experience: body, society and nature. These are: the ethics of the species [J. Habermas], the ethics of liberation [E. Dussel] and the ethics of the responsibility [H. Jonas]. This material argument is a philosophical foundation to considering for three types of applied ethics: medical bioethics, development ethics and environmental ethics. PMID:20405971

  15. Nutritional Systems Biology

    DEFF Research Database (Denmark)

    Jensen, Kasper

    and network biology has the potential to increase our understanding of how small molecules affect metabolic pathways and homeostasis, how this perturbation changes at the disease state, and to what extent individual genotypes contribute to this. A fruitful strategy in approaching and exploring the field...... of nutritional research is, therefore, to borrow methods that are well established in medical and pharmacological research. In this thesis, we use advanced data-mining tools for the construction of a database with available, state-of-the-art information concerning the interaction of food and its molecular...

  16. Illuminating Cell Biology

    Science.gov (United States)

    2002-01-01

    NASA's Ames Research Center awarded Ciencia, Inc., a Small Business Innovation Research contract to develop the Cell Fluorescence Analysis System (CFAS) to address the size, mass, and power constraints of using fluorescence spectroscopy in the International Space Station's Life Science Research Facility. The system will play an important role in studying biological specimen's long-term adaptation to microgravity. Commercial applications for the technology include diverse markets such as food safety, in situ environmental monitoring, online process analysis, genomics and DNA chips, and non-invasive diagnostics. Ciencia has already sold the system to the private sector for biosensor applications.

  17. Biological hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Benemann, J.R. [Univ. of California, Berkeley, CA (United States)

    1995-11-01

    Biological hydrogen production can be accomplished by either thermochemical (gasification) conversion of woody biomass and agricultural residues or by microbiological processes that yield hydrogen gas from organic wastes or water. Biomass gasification is a well established technology; however, the synthesis gas produced, a mixture of CO and H{sub 2}, requires a shift reaction to convert the CO to H{sub 2}. Microbiological processes can carry out this reaction more efficiently than conventional catalysts, and may be more appropriate for the relatively small-scale of biomass gasification processes. Development of a microbial shift reaction may be a near-term practical application of microbial hydrogen production.

  18. Biological Traits of Botrytis cinerea Pers. Isolates Differently Sensitive to Dicarboximides

    Directory of Open Access Journals (Sweden)

    Brankica Tanović

    2007-01-01

    Full Text Available A study of biological characteristics of both field and laboratory isolates revealed that highly resistant isolates were morphologically different from their original wild types. The majority of them were less pathogenic and produced less sclerotia than the original ones.Significant negative correlation between osmotic sensitivity and the degree of resistance was recorded. The correlation between micelium growth rate and resistance to dicarboximides was also significant and negative. Growth medium, acidity and growth temperature had less effect on the micelium growth rate of the highly resistant isolates than on the sensitive ones.

  19. From biologically-inspired physics to physics-inspired biology From biologically-inspired physics to physics-inspired biology

    Science.gov (United States)

    Kornyshev, Alexei A.

    2010-10-01

    couple of billion years of evolutionary history; 'you cannot expect to explain so wise an old bird in a few simple words'. It is indisputably so, but it is followed by two other competing sub-dogmas: Dogma N6a: Physics wants to simplify and unify things, as much as possible, biology resists the reductionist approach and is happy about diversification and complexity. In my opinion all these dogmas have been beaten by this icon, the understanding of which gave rise to the idea of DNA replication and all the following principles of molecular biology. Not only 'this will happen again' but on a smaller scale this happens all the time. Generally, through centuries, physics and mathematics have changed our lives completely. In a short article one cannot give a full list of such achievements from Aristotle's time, but I name just a few of the summits of the last two centuries. A great physicist Rutherford (who was, by the way, a Nobel Laureate in Chemistry for 'his investigations into the disintegration of the elements, and the chemistry of radioactive substances') was also famous for an extreme (and definitely outdated) statement: 'All science is either stamp collecting or physics'. Let us paraphrase him and collect some stamps. I have no space to stop on the Faraday-Ampere laws of stationary electricity (who cares, electric current comes from a plug would be the answer of most of people unfamiliar with physics, and forget about electricity that is supplied to biological laboratories). So, let us go straight away to James Clerk Maxwell. He derived four equations that related electricity and magnetism and, as the legend tells us, it took him seven years to write the fourth equation to complete the set with four unknown variables. The story of the fourth Maxwell equation is one of the most dramatic stories in the history of science [4]. As a solution of that set he obtained relativistically-invariant electromagnetic waves, which no one saw and the consequences of which no one had

  20. Effect of Glyphosate on Symbiotic N2 Fixation and Nickel Concentration in Glyphosate-Resistant Soybean

    Science.gov (United States)

    The impact of widespread cultivation of glyphosate-resistant (GR) soybean and the use of one herbicide class on biological processes has received considerable attention. Decreased biological nitrogen fixation in GR soybean has been attributed directly to toxicity of glyphosate or its metabolites to ...

  1. Fitness cost in field and laboratory Aedes aegypti populations associated with resistance to the insecticide temephos

    OpenAIRE

    Diniz, Diego Felipe Araujo; de Melo-Santos, Maria Alice Varjal; Santos, Eloína Maria de Mendonça; Beserra, Eduardo Barbosa; Helvecio, Elisama; de Carvalho-Leandro, Danilo; dos Santos, Bianka Santana; de Menezes Lima, Vera Lúcia; Ayres, Constância Flávia Junqueira

    2015-01-01

    Background The continued use of chemical insecticides in the context of the National Program of Dengue Control in Brazil has generated a high selective pressure on the natural populations of Aedes aegypti, leading to their resistance to these compounds in the field. Fitness costs have been described as adaptive consequences of resistance. This study evaluated the biological and reproductive performance of A. aegypti strains and a field population resistant to temephos, the main larvicide used...

  2. Resistance to bio-insecticides or how to enhance their sustainability: a review

    OpenAIRE

    Myriam eSIEGWART; Benoit eGraillot; Christine eBlachère-Lopez; Samantha eBesse; Marc eBardin; Philippe eNicot; Miguel eLopez-Ferber

    2015-01-01

    After more than 70 years of chemical pesticide use, modern agriculture is increasingly using biological control products. Resistances to conventional insecticides are wide spread, while those to bio-insecticides have raised less attention, and resistance management is frequently neglected. However, a good knowledge of the limitations of a new technique often provides greater sustainability. In this review, we compile cases of resistance to widely used bio-insecticides and describe the associa...

  3. A pivot mutation impedes reverse evolution across an adaptive landscape for drug resistance in Plasmodium vivax

    OpenAIRE

    Ogbunugafor, C. Brandon; Hartl, Daniel

    2016-01-01

    Background: The study of reverse evolution from resistant to susceptible phenotypes can reveal constraints on biological evolution, a topic for which evolutionary theory has relatively few general principles. The public health catastrophe of antimicrobial resistance in malaria has brought these constraints on evolution into a practical realm, with one proposed solution: withdrawing anti-malarial medication use in high resistance settings, built on the assumption that reverse evolution occurs ...

  4. Regicide and Resistance

    DEFF Research Database (Denmark)

    Flohr, Mikkel

    2016-01-01

    This article examines the role of resistance in Michel Foucault’s political thought. The article recovers this otherwise obscured aspect of Foucault’s thought through a systematic analysis of his theoretical regicide and consequent reconceptualization of power, agency and resistance. It is argued...... that Foucault developed a highly original account of resistance, which was, and should continue to be considered, central to his thought and its critical potential. It is shown how Foucault’s concept of resistance overcomes the limitation of voluntarism and determinism, which continue to mare contemporary...... political theory, providing a passage from the critique of contemporary configurations of power to the irrepressible possibility that they may be contested and changed....

  5. Insulin Resistance and Prediabetes

    Science.gov (United States)

    ... Disease Organizations (PDF, 293 KB). Alternate Language URL Insulin Resistance and Prediabetes Page Content On this page: ... Nutrition Points to Remember Clinical Trials What is insulin? Insulin is a hormone made in the pancreas, ...

  6. Steroid resistant asthma.

    Science.gov (United States)

    Luhadia, S K

    2014-03-01

    Inspite of very safe and effective treatment, Bronchial asthmatics do not respond well in 5-10% of cases which are labelled as Refractory Asthma. Besides compliance, presence of psychogenic and trigger factors and comorbid illness, steroid insensitiveness or resistance may play a significant role in the poorly controlled/responding asthmatics. Type I Steroid resistance is due to lack of binding affinity of steroids to glucocorticoid receptors and may respond to higher doses of steroids while type II steroid resistance is because of reduced number of cells with glucocorticoid receptors, which is very rare and do not respond to even higher doses of systemic steroids and these cases require alternative/novel therapies. Future treatment of steroid resistant and severe refractory asthma is likely to be targeted towards cytokines and Bronchial Thermoplasty.

  7. Skid Resistance Research

    Science.gov (United States)

    1977-01-01

    Skidding causes many traffic accidents. Streets and highways with skid-resisting surfaces reduce the incidence of such accidents. In fact, resurfacing roads to improve skid resistance is now required by federal law. Skid resistance is measured by road testing with specially equipped skid trailers. A project underway at NASA-Langley may considerably reduce the cost of skid trailers, thus making them more widely available to highway departments. For testing the skid resistance of aircraft runways, Langley engineers developed a relatively inexpensive test vehicle and a "pulsed braking" technique that is now being applied experimentally to road testing. The vehicle is a standard automobile modified to incorporate instrumentation, special test tires and valves, and a trailing fifth wheel for monitoring distance and velocity. The instrumentation includes a low-cost meter, a set of accelerometers that sense motion changes, and a chart recorder.

  8. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... use of antimicrobial drugs will result in the development of resistant strains of bacteria, complicating clinician's efforts ... Emergency Preparedness International Programs News & Events Training & Continuing Education Inspections & Compliance Federal, State & Local Officials Consumers Health ...

  9. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... resistance more real and understandable to veterinarians, livestock producers, lawmakers, consumer representatives and other key audiences. We ... Regulatory Information Safety Emergency Preparedness International Programs News & ... Training & Continuing Education Inspections & Compliance Federal, State & Local ...

  10. Solvent resistant nanofiltration membranes

    OpenAIRE

    Dutczak, Szymon Maria

    2011-01-01

    This thesis describes preparation and characterization of membranes for organic solvent filtration (OSF). The main aim was developing membranes for solvent resistant nanofiltration (SRNF) with molecular weight cut-off below 500 g mol-1.

  11. Resistance to Therapy.

    Science.gov (United States)

    Rivera, Gabriel; Wakelee, Heather A

    2016-01-01

    Identification of driver mutations in adenocarcinoma of the lung has revolutionized the treatment of this disease. It is now standard of care to look for activating mutations in epidermal growth factor receptor (EGFR), and translocations in anaplastic lymphoma kinase (ALK) or ROS1 in all newly diagnosed adenocarcinoma of the lung, and in many patients with squamous cell carcinoma as well. Recognition of multiple other lung cancer driver mutations has also expanded treatment options. Targeted treatments of these mutations lead to rapid and prolonged responses, but resistance inevitably develops. Until recently, traditional chemotherapy was the only alternative at that time, but better understanding of resistance mechanisms has lead to additional therapeutic options. These mechanisms of resistance and treatments are the focus of this chapter. Understanding of mechanisms of chemotherapy resistance is touched upon, along with a brief discussion of immune checkpoint inhibitors. PMID:27535395

  12. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... issue of antimicrobial resistance is that the subject material appears abstract and is complex. This video was ... can develop and spread. All FDA CVM produced material may be copied, reproduced, and distributed as long ...

  13. Antimicrobial (Drug) Resistance: Gonorrhea

    Science.gov (United States)

    ... Marketing Share this: Main Content Area Multidrug-Resistant Neisseria gonorrhoeae (Gonorrhea) During the past 50 years, the use ... Gonorrhea is a sexually transmitted disease caused by Neisseria gonorrhoeae , a bacterium that can infect areas of the ...

  14. Toxins for Transgenic Resistance to Hemipteran Pests

    Directory of Open Access Journals (Sweden)

    Bryony C. Bonning

    2012-06-01

    Full Text Available The sap sucking insects (Hemiptera, which include aphids, whiteflies, plant bugs and stink bugs, have emerged as major agricultural pests. The Hemiptera cause direct damage by feeding on crops, and in some cases indirect damage by transmission of plant viruses. Current management relies almost exclusively on application of classical chemical insecticides. While the development of transgenic crops expressing toxins derived from the bacterium Bacillus thuringiensis (Bt has provided effective plant protection against some insect pests, Bt toxins exhibit little toxicity against sap sucking insects. Indeed, the pest status of some Hemiptera on Bt-transgenic plants has increased in the absence of pesticide application. The increased pest status of numerous hemipteran species, combined with increased prevalence of resistance to chemical insecticides, provides impetus for the development of biologically based, alternative management strategies. Here, we provide an overview of approaches toward transgenic resistance to hemipteran pests.

  15. Antiviral resistance: influenza B

    OpenAIRE

    Conde, Patrícia; Guiomar, Raquel; Cristóvão, Paula; Pechirra, Pedro

    2013-01-01

    Currently circulating influenza viruses are resistant to adamantanes and except for a low number of sporadic cases most are sensitive to neuraminidase inhibitors (NI). Adamantanes are ineffective against influenza B viruses and although NI-resistant influenza B viruses have been rarely reported, recently in the United States was identified one cluster of influenza B viruses with reduced susceptibility to NI and with the I221V substitution in the active site of the neuraminidase. Despite the l...

  16. Antimicrobial resistance in wildlife

    OpenAIRE

    Vittecoq, M.; Godreuil, S.; Prugnolle, Franck; Durand, P.; Brazier, L; Renaud, N; Arnal, A.; Aberkane, S.; Jean-Pierre, H.; Gauthier-Clerc, M; Thomas, F.; Renaud, F.

    2016-01-01

    The spread of antimicrobial resistance is of major concern for human health and leads to growing economic costs. While it is increasingly hypothesized that wildlife could play an important role in antimicrobial-resistant bacteria dynamics, empirical data remain scarce. The present work builds on a systematic review of the available data in order to highlight the main information we have and to suggest research pathways that should be followed if we aim to fill the gaps in our current knowledg...

  17. Stab resistant body armour

    OpenAIRE

    Horsfall, Ian

    2000-01-01

    There is now a widely accepted need for stab resistant body armour for the police in the UK. However, very little research has been done on knife resistant systems and the penetration mechanics of sharp projectiles are poorly understood. This thesis explores the general background to knife attack and defence with a particular emphasis on the penetration mechanics of edged weapons. The energy and velocity that can be achieved in stabbing actions has been determined for a numb...

  18. Male mating biology

    Directory of Open Access Journals (Sweden)

    Howell Paul I

    2009-11-01

    Full Text Available Abstract Before sterile mass-reared mosquitoes are released in an attempt to control local populations, many facets of male mating biology need to be elucidated. Large knowledge gaps exist in how both sexes meet in space and time, the correlation of male size and mating success and in which arenas matings are successful. Previous failures in mosquito sterile insect technique (SIT projects have been linked to poor knowledge of local mating behaviours or the selection of deleterious phenotypes during colonisation and long-term mass rearing. Careful selection of mating characteristics must be combined with intensive field trials to ensure phenotypic characters are not antagonistic to longevity, dispersal, or mating behaviours in released males. Success has been achieved, even when colonised vectors were less competitive, due in part to extensive field trials to ensure mating compatibility and effective dispersal. The study of male mating biology in other dipterans has improved the success of operational SIT programmes. Contributing factors include inter-sexual selection, pheromone based attraction, the ability to detect alterations in local mating behaviours, and the effects of long-term colonisation on mating competitiveness. Although great strides have been made in other SIT programmes, this knowledge may not be germane to anophelines, and this has led to a recent increase in research in this area.

  19. Neutron instrumentation for biology

    Energy Technology Data Exchange (ETDEWEB)

    Mason, S.A. [Institut Laue-Langevin, Grenoble (France)

    1994-12-31

    In the October 1994 round of proposals at the ILL, the external biology review sub- committee was asked to allocate neutron beam time to a wide range of experiments, on almost half the total number of scheduled neutron instruments: on 3 diffractometers, on 3 small angle scattering instruments, and on some 6 inelastic scattering spectrometers. In the 3.5 years since the temporary reactor shutdown, the ILL`s management structure has been optimized, budgets and staff have been trimmed, the ILL reactor has been re-built, and many of the instruments up-graded, many powerful (mainly Unix) workstations have been introduced, and the neighboring European Synchrotron Radiation Facility has established itself as the leading synchrotron radiation source and has started its official user program. The ILL reactor remains the world`s most intense dedicated neutron source. In this challenging context, it is of interest to review briefly the park of ILL instruments used to study the structure and energetics of small and large biological systems. A brief summary will be made of each class of experiments actually proposed in the latest ILL proposal round.

  20. Oscillations in Mathematical Biology

    CERN Document Server

    1983-01-01

    The papers in this volume are based on talks given at a one day conference held on the campus of Adelphi University in April 1982. The conference was organized with the title "Oscillations in Mathematical Biology;" however the speakers were allowed considerable latitutde in their choice of topics. In the event, the talks all concerned the dynamics of non-linear systems arising in biology so that the conference achieved a good measure of cohesion. Some of the speakers cho~e not to submit a manuscript for these proceedings, feeling that their material was too conjectural to be committed to print. Also the paper of Rinzel and Troy is a distillation of the two separate talks that the authors gave. Otherwise the material reproduces the conference proceedings. The conference was made possible by the generous support of the Office of the Dean of the College of Arts and Sciences at Adelphi. The bulk of the organization of the conference was carried out by Dr. Ronald Grisell whose energy was in large measure responsib...

  1. Computational Biology and the Limits of Shared Vision

    DEFF Research Database (Denmark)

    Carusi, Annamaria

    2011-01-01

    Several studies have focused on the social sharing of visual practices as constitutive of evidence within a domain, while there has been relatively less attention paid to points where the social sharing of practices breaks down, or is resisted. This article argues that a study of both types...... of cases is necessary in order to gain a better perspective on social sharing of practices, and on what other factors this sharing is dependent upon. The article presents the case of currently emerging inter-disciplinary visual practices in the domain of computational biology, where the sharing of visual...... practices would be beneficial to the collaborations necessary for the research. Computational biology includes sub-domains where visual practices are coming to be shared across disciplines, and those where this is not occurring, and where the practices of others are resisted. A significant point...

  2. Mathematical modeling of biological processes

    CERN Document Server

    Friedman, Avner

    2014-01-01

    This book on mathematical modeling of biological processes includes a wide selection of biological topics that demonstrate the power of mathematics and computational codes in setting up biological processes with a rigorous and predictive framework. Topics include: enzyme dynamics, spread of disease, harvesting bacteria, competition among live species, neuronal oscillations, transport of neurofilaments in axon, cancer and cancer therapy, and granulomas. Complete with a description of the biological background and biological question that requires the use of mathematics, this book is developed for graduate students and advanced undergraduate students with only basic knowledge of ordinary differential equations and partial differential equations; background in biology is not required. Students will gain knowledge on how to program with MATLAB without previous programming experience and how to use codes in order to test biological hypothesis.

  3. Protein microarrays for systems biology

    Institute of Scientific and Technical Information of China (English)

    Lina Yang; Shujuan Guo; Yang Li; Shumin Zhou; Shengce Tao

    2011-01-01

    Systems biology holds the key for understanding biological systems on a system level. It eventually holds the key for the treatment and cure of complex diseases such as cancer,diabetes, obesity, mental disorders, and many others. The '-omics' technologies, such as genomics, transcriptomics,proteomics, and metabonomics, are among the major driving forces of systems biology. Featured as highthroughput, miniaturized, and capable of parallel analysis,protein microarrays have already become an important technology platform for systems biology, In this review, we will focus on the system level or global analysis of biological systems using protein microarrays. Four major types of protein microarrays will be discussed: proteome microarrays, antibody microarrays, reverse-phase protein arrays,and lectin microarrays. We will also discuss the challenges and future directions of protein microarray technologies and their applications for systems biology. We strongly believe that protein microarrays will soon become an indispensable and invaluable tool for systems biology.

  4. Microgravity Fluids for Biology, Workshop

    Science.gov (United States)

    Griffin, DeVon; Kohl, Fred; Massa, Gioia D.; Motil, Brian; Parsons-Wingerter, Patricia; Quincy, Charles; Sato, Kevin; Singh, Bhim; Smith, Jeffrey D.; Wheeler, Raymond M.

    2013-01-01

    Microgravity Fluids for Biology represents an intersection of biology and fluid physics that present exciting research challenges to the Space Life and Physical Sciences Division. Solving and managing the transport processes and fluid mechanics in physiological and biological systems and processes are essential for future space exploration and colonization of space by humans. Adequate understanding of the underlying fluid physics and transport mechanisms will provide new, necessary insights and technologies for analyzing and designing biological systems critical to NASAs mission. To enable this mission, the fluid physics discipline needs to work to enhance the understanding of the influence of gravity on the scales and types of fluids (i.e., non-Newtonian) important to biology and life sciences. In turn, biomimetic, bio-inspired and synthetic biology applications based on physiology and biology can enrich the fluid mechanics and transport phenomena capabilities of the microgravity fluid physics community.

  5. Changing Trends in Resistance Pattern of Methicillin Resistant Staphylococcus aureus

    OpenAIRE

    Kali, Arunava; Stephen, Selvaraj; Umadevi, Sivaraman; Kumar, Shailesh; Joseph, Noyal Mariya; Srirangaraj, Sreenivasan

    2013-01-01

    Background: Methicillin resistance in Staphylococcus aureus is associated with multidrug resistance, an aggressive course, increased mortality and morbidity in both community and health care facilities. Monitoring of newly emerging and prevalent Methicillin Resistant Staphylococcus aureus (MRSA) strains for their resistance patterns to conventional as well as novel drugs, are essential for infection control.

  6. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... About FDA Contact FDA Browse by Product Area Product Areas back Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products

  7. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Health and Human Services FDA U.S. Food and Drug Administration Protecting and Promoting Your Health A to ... Search FDA Submit search Popular Content Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics ...

  8. Chemical and biological insecticides select distinct gene expression patterns in Aedes aegypti mosquito.

    Science.gov (United States)

    Després, Laurence; Stalinski, Renaud; Faucon, Frédéric; Navratil, Vincent; Viari, Alain; Paris, Margot; Tetreau, Guillaume; Poupardin, Rodolphe; Riaz, Muhammad Asam; Bonin, Aurélie; Reynaud, Stéphane; David, Jean-Philippe

    2014-12-01

    Worldwide evolution of mosquito resistance to chemical insecticides represents a major challenge for public health, and the future of vector control largely relies on the development of biological insecticides that can be used in combination with chemicals (integrated management), with the expectation that populations already resistant to chemicals will not become readily resistant to biological insecticides. However, little is known about the metabolic pathways affected by selection with chemical or biological insecticides. Here we show that Aedes aegypti, a laboratory mosquito strain selected with a biological insecticide (Bacillus thuringiensis israelensis, Bti) evolved increased transcription of many genes coding for endopeptidases while most genes coding for detoxification enzymes were under-expressed. By contrast, in strains selected with chemicals, genes encoding detoxification enzymes were mostly over-expressed. In all the resistant strains, genes involved in immune response were under-transcribed, suggesting that basal immunity might be a general adjustment variable to compensate metabolic costs caused by insecticide selection. Bioassays generally showed no evidence for an increased susceptibility of selected strains towards the other insecticide type, and all chemical-resistant strains were as susceptible to Bti as the unselected parent strain, which is a good premise for sustainable integrated management of mosquito populations resistant to chemicals.

  9. Shame, classroom resistance, and Bion’s desire not to know

    Directory of Open Access Journals (Sweden)

    Marshall Alcorn

    2011-12-01

    Full Text Available It is not uncommon for students to resist evidence or claims taught by their teachers. This paper uses affect theory from the work of Sylvan Tomkins to understand Wilfred Bion’s account of the human “desire not to know.” I argue that cultural experiences with shame and disgust set in place biological responses that restrict and attack possibilities for cognitive thought. Classroom experiences that appeal to requirements for “thoughtfulness” should anticipate the biological ground of resistances and seek forms of engagement that respond to resistance through emotional rather than intellectual force.

  10. On Biology and Technology: The Economics of Managing Biotechnologies

    OpenAIRE

    Goeschl, Timo; Swanson, Timothy

    2003-01-01

    This paper considers those sectors of the economy that operate under the same regimes of rewarding private innovators as others, but differ in that they face recurring problems of resistance, as occur in the pharmaceutical and agricultural industries. This recurrence originates in the natural processes of selection and evolution among humanity’s biological competitors. The paper examines the capacity for decentralised patent-based incentive mechanisms to result in socially optimal outcomes in...

  11. Evolution in invasive plants: implications for biological control

    OpenAIRE

    Müller-Schärer, Heinz; Schaffner, Urs; Steinger, Thomas

    2005-01-01

    Evidence is increasing that invasive plants can undergo rapid adaptive evolution during the process of range expansion. Here, we argue that evolutionary change during invasions will also affect plant–antagonist inter-actions and, thus, will have important implications for biological control programmes targeted at invasive plants. We explore how altered selection in the new range might influence the evolution of plant defence (resistance and tolerance) and life history. The degree to which suc...

  12. Linezolid resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Pavani Gandham

    2014-08-01

    Full Text Available Linezolid is the only antibiotic available as an oral formulation for resistant staphylococcal infections. It is effective in skin and soft tissue infections, nosocomial pneumonias including VAP, infective endocarditis and MRSA meningitis. It is also effective in the eradication of both nasal and throat colonization of MRSA. Its high bioavailability and post antibiotic effect, ease of switching to oral therapy during its use and the fact that it can be used in patients of all ages, also in patients with liver disease and poor kidney function and its increased effectiveness over glycopeptides makes this drug a precious drug in the treatment of resistant staphylococcal infections. Linezolid resistance in staphylococcus is defined as a linezolid MIC of and #8805;8 mg/L. Reported Linezolid resistance in India and elsewhere is 2-20%. There is clonal dissemination of Linezolid Resistant Staphylococcus aureus (LRSA within or across health care settings which demands continuous surveillance to determine the emergent risk of resistance strains and to establish guidelines for appropriate use. Clinical laboratories should confirm any LRSA preferably by a second method, prior to using linezolid for serious infections. Effective surveillance, more judicious use of this antibiotic, avoiding linezolid usage for empiric therapy in hospital acquired staphylococcus infections, optimization of the pharmacological parameters of the antibiotics in specific clinical situation, decreasing bacterial load by timely surgical debridement or drainage of collections, use of combination therapies would prevent the emergence of resistance to linezolid in staphylococcus aureus. [Int J Res Med Sci 2014; 2(4.000: 1253-1256

  13. ADVANCE IN RESEARCH ON DROUGHT RESISTANCE OF POPULUS%杨树抗旱性研究进展

    Institute of Scientific and Technical Information of China (English)

    尹春英; 李春阳

    2003-01-01

    The drought resistance of woody plants, in particular, Populus, was reviewed in this paper. Studies about drought resistance of Populus mostly focused on changes in growth properties, physiological adaptation and biochemical aspects, but a few on molecular biology. The indexes of drought adaptation and productivity were analyzed and these indexes could be employed to identify drought resistance of woody plants. Combination of such different approaches will, hopefully, give us a more complete understanding of the various regulatory mechanisms in trees than what we may have today. With development of the molecular biology of woody plants, the sluties on stress resistance of Populus which was regarded as a model plant, are summarised. Ref 96

  14. Biology of Sexual Dysfunction

    Directory of Open Access Journals (Sweden)

    Anil Kumar Mysore Nagaraj

    2009-05-01

    Full Text Available Sexual activity is a multifaceted activity, involving complex interactions between the nervous system, the endocrine system, the vascular system and a variety of structures that are instrumental in sexual excitement, intercourse and satisfaction. Sexual function has three components i.e., desire, arousal and orgasm. Many sexual dysfunctions can be categorized according to the phase of sexual response that is affected. In actual clinical practice however, sexual desire, arousal and orgasmic difficulties more often than not coexist, suggesting an integration of phases. Sexual dysfunction can result from a wide variety of psychological and physiological causes including derangements in the levels of sex hormones and neurotrensmitters. This review deals with the biology of different phases of sexual function as well as implications of hormones and neurotransmitters in sexual dysfunction

  15. Neutron structural biology

    Energy Technology Data Exchange (ETDEWEB)

    Niimura, Nobuo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    Neutron diffraction provides an experimental method of directly locating hydrogen atoms in protein which play important roles in physiological functions. However, there are relatively few examples of neutron crystallography in biology since it takes a lot of time to collect a sufficient number of Bragg reflections due to the low flux of neutrons illuminating the sample. In order to overcome the flux problem, we have successfully developed the neutron IP, where the neutron converter, {sup 6}Li or Gd, was mixed with a photostimulated luminescence material on flexible plastic support. Neutron Laue diffraction 2A data from tetragonal lysozyme were collected for 10 days with neutron imaging plates, and 960 hydrogen atoms in the molecule and 157 bound water molecules were identified. These results explain the proposed hydrolysis mechanism of the sugar by the lysozyme molecule and that lysozyme is less active at pH7.0. (author)

  16. Plant Vascular Biology 2010

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Biao

    2014-11-17

    This grant supported the Second International Conference on Plant Vascular Biology (PVB 2010) held July 24-28, 2010 on the campus of Ohio State University, Columbus, Ohio. Biao Ding (Ohio State University; OSU) and David Hannapel (Iowa State University; ISU) served as co-chairs of this conference. Biao Ding served as the local organizer. PVB is defined broadly here to include studies on the biogenesis, structure and function of transport systems in plants, under conditions of normal plant growth and development as well as of plant interactions with pathogens. The transport systems cover broadly the xylem, phloem, plasmodesmata and vascular cell membranes. The PVB concept has emerged in recent years to emphasize the integrative nature of the transport systems and approaches to investigate them.

  17. Biological effects of neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Ogiu, Toshiaki; Ohmachi, Yasushi; Ishida, Yuka [National Inst. of Radiological Sciences, Chiba (JP)] [and others

    2003-03-01

    Although the occasion to be exposed to neutrons is rare in our life, except for nuclear accidents like in the critical accident at Tokai-mura in 1999, countermeasures against accident should be always prepared. In the Tokai-mura accident, residents received less than 21 mSv of neutrons and gamma rays. The cancer risks and fetal effects of low doses of neutrons were matters of concern among residents. The purpose of this program is to investigate the relative biological effectiveness (RBE) for leukemias, and thereby to assess risks of neutrons. Animal experiments are planed to obtain the following RBEs: (1) RBE for the induction of leukemias in mice and (2) RBE for effects on fetuses. Cyclotron fast neutrons (10 MeV) and electrostatic accelerator-derived neutrons (2 MeV) are used for exposure in this program. Furthermore, cytological and cytogenetic analyses will be performed. (author)

  18. The biology of strigolactones

    KAUST Repository

    Ruyter-Spira, Carolien P.

    2013-02-01

    The strigolactones are rhizosphere signaling molecules as well as a new class of plant hormones with a still increasing number of biological functions being uncovered. Here, we review a recent major breakthrough in our understanding of strigolactone biosynthesis, which has revealed the unexpected simplicity of the originally postulated complex pathway. Moreover, the discovery and localization of a strigolactone exporter sheds new light on putative strigolactone fluxes to the rhizosphere as well as within the plant. The combination of these data with information on the expression and regulation of strigolactone biosynthetic and downstream signaling genes provides new insights into how strigolactones control the many different aspects of plant development and how their rhizosphere signaling role may have evolved. © 2012 Elsevier Ltd.

  19. Networks in Cell Biology

    Science.gov (United States)

    Buchanan, Mark; Caldarelli, Guido; De Los Rios, Paolo; Rao, Francesco; Vendruscolo, Michele

    2010-05-01

    Introduction; 1. Network views of the cell Paolo De Los Rios and Michele Vendruscolo; 2. Transcriptional regulatory networks Sarath Chandra Janga and M. Madan Babu; 3. Transcription factors and gene regulatory networks Matteo Brilli, Elissa Calistri and Pietro Lió; 4. Experimental methods for protein interaction identification Peter Uetz, Björn Titz, Seesandra V. Rajagopala and Gerard Cagney; 5. Modeling protein interaction networks Francesco Rao; 6. Dynamics and evolution of metabolic networks Daniel Segré; 7. Hierarchical modularity in biological networks: the case of metabolic networks Erzsébet Ravasz Regan; 8. Signalling networks Gian Paolo Rossini; Appendix 1. Complex networks: from local to global properties D. Garlaschelli and G. Caldarelli; Appendix 2. Modelling the local structure of networks D. Garlaschelli and G. Caldarelli; Appendix 3. Higher-order topological properties S. Ahnert, T. Fink and G. Caldarelli; Appendix 4. Elementary mathematical concepts A. Gabrielli and G. Caldarelli; References.

  20. A Biologically Inspired Classifier

    CERN Document Server

    Bagnoli, Franco

    2007-01-01

    We present a method for measuring the distance among records based on the correlations of data stored in the corresponding database entries. The original method (F. Bagnoli, A. Berrones and F. Franci. Physica A 332 (2004) 509-518) was formulated in the context of opinion formation. The opinions expressed over a set of topic originate a ``knowledge network'' among individuals, where two individuals are nearer the more similar their expressed opinions are. Assuming that individuals' opinions are stored in a database, the authors show that it is possible to anticipate an opinion using the correlations in the database. This corresponds to approximating the overlap between the tastes of two individuals with the correlations of their expressed opinions. In this paper we extend this model to nonlinear matching functions, inspired by biological problems such as microarray (probe-sample pairing). We investigate numerically the error between the correlation and the overlap matrix for eight sequences of reference with r...

  1. Platelets in Lung Biology

    Science.gov (United States)

    Weyrich, Andrew S.; Zimmerman, Guy A.

    2013-01-01

    Platelets and the lungs have an intimate relationship. Platelets are anucleate mammalian blood cells that continuously circulate through pulmonary vessels and that have major effector activities in hemostasis and inflammation. The lungs are reservoirs for megakaryocytes, the requisite precursor cell in thrombopoiesis, which is the intricate process by which platelets are generated. Platelets contribute to basal barrier integrity of the alveolar capillaries, which selectively restricts the transfer of water, proteins, and red blood cells out of the vessels. Platelets also contribute to pulmonary vascular repair. Although platelets bolster hemostatic and inflammatory defense of the healthy lung, experimental evidence and clinical evidence indicate that these blood cells are effectors of injury in a variety of pulmonary disorders and syndromes. Newly discovered biological capacities of platelets are being explored in the context of lung defense, disease, and remodeling. PMID:23043249

  2. [Biological therapy for osteoporosis].

    Science.gov (United States)

    Nakamura, Shinya; Tanaka, Sakae

    2014-06-01

    Osteoporosis is a disorder of bone formation and resorption balance. Advances in our knowledge of the molecular mechanisms of bone formation and resorption led to promising therapeutic targets for osteoporosis. In the novel biological drugs, denosumab, a monoclonal antibody against receptor activator of nuclear factor-κB ligand (RANKL) has been clinically applied by positive effect on bone mineral density, negative effect on bone resorption, preventive effect on fragility fractures and safety. Odanacatib, a cathepsin K inhibitor is drawing attention as an antiresorptive drug which has lower bone resorption potency than bisphosphoneate. On the other hand, BHQ-880, an anti-Dickkopf-1 (Dkk-1) antibody and romosozumab (AMG-785) , an anti-sclerostin antibody which activate Wnt/β-catenin signaling pathway are drawing attention as bone formation accelerators with no bone resorption acceleration. Clinical studies of these drugs are now ongoing and their clinical applications are expected. PMID:24870844

  3. Biological signals as handicaps.

    Science.gov (United States)

    Grafen, A

    1990-06-21

    An ESS model of Zahavi's handicap principle is constructed. This allows a formal exposition of how the handicap principle works, and shows that its essential elements are strategic. The handicap model is about signalling, and it is proved under fairly general conditions that if the handicap principle's conditions are met, then an evolutionarily stable signalling equilibrium exists in a biological signalling system, and that any signalling equilibrium satisfies the conditions of the handicap principle. Zahavi's major claims for the handicap principle are thus vindicated. The place of cheating is discussed in view of the honesty that follows from the handicap principle. Parallel signalling models in economics are discussed. Interpretations of the handicap principle are compared. The models are not fully explicit about how females use information about male quality, and, less seriously, have no genetics. A companion paper remedies both defects in a model of the handicap principle at work in sexual selection. PMID:2402153

  4. Evolutionary biology of cancer.

    Science.gov (United States)

    Crespi, Bernard; Summers, Kyle

    2005-10-01

    Cancer is driven by the somatic evolution of cell lineages that have escaped controls on replication and by the population-level evolution of genes that influence cancer risk. We describe here how recent evolutionary ecological studies have elucidated the roles of predation by the immune system and competition among normal and cancerous cells in the somatic evolution of cancer. Recent analyses of the evolution of cancer at the population level show how rapid changes in human environments have augmented cancer risk, how strong selection has frequently led to increased cancer risk as a byproduct, and how anticancer selection has led to tumor-suppression systems, tissue designs that slow somatic evolution, constraints on morphological evolution and even senescence itself. We discuss how applications of the tools of ecology and evolutionary biology are poised to revolutionize our understanding and treatment of this disease.

  5. Robust Design of Biological Circuits: Evolutionary Systems Biology Approach

    OpenAIRE

    Bor-Sen Chen; Chih-Yuan Hsu; Jing-Jia Liou

    2011-01-01

    Artificial gene circuits have been proposed to be embedded into microbial cells that function as switches, timers, oscillators, and the Boolean logic gates. Building more complex systems from these basic gene circuit components is one key advance for biologic circuit design and synthetic biology. However, the behavior of bioengineered gene circuits remains unstable and uncertain. In this study, a nonlinear stochastic system is proposed to model the biological systems with intrinsic parameter ...

  6. Biology and management of grape phylloxera.

    Science.gov (United States)

    Granett, J; Walker, M A; Kocsis, L; Omer, A D

    2001-01-01

    Grape phylloxera, Daktulosphaira vitifoliae (Homoptera: Phylloxeridae), is a worldwide pest of grapevines. Its life cycle has sexual and asexual portions with forms that feed from leaf and root galls. Not all forms occur throughout the insect's range. Root forms predominate on Vitis vinifera cultivars; leaf forms predominate on other Vitis species characteristic of the American native range. Other conditions influence expression of the life cycle. Hosts and conditions similarly affect life table performance. Damage to grapevines is by secondary soilborne pathogens attacking the feeding site and by physiological interaction of the insect with the grapevine, though the latter has not been well studied. Resistant rootstocks derived from native American Vitis are the primary control tool. The insect varies genetically and relative to performance on hosts. Use of insecticides is limited in effect, and other control methods are not proven. More research on the biology, ecology, and management of phylloxera is needed. PMID:11112174

  7. Antibiotic resistance in wild birds.

    Science.gov (United States)

    Bonnedahl, Jonas; Järhult, Josef D

    2014-05-01

    Wild birds have been postulated as sentinels, reservoirs, and potential spreaders of antibiotic resistance. Antibiotic-resistant bacteria have been isolated from a multitude of wild bird species. Several studies strongly indicate transmission of resistant bacteria from human rest products to wild birds. There is evidence suggesting that wild birds can spread resistant bacteria through migration and that resistant bacteria can be transmitted from birds to humans and vice versa. Through further studies of the spatial and temporal distribution of resistant bacteria in wild birds, we can better assess their role and thereby help to mitigate the increasing global problem of antibiotic resistance. PMID:24697355

  8. Clopidogrel Resistance: Current Issues

    Directory of Open Access Journals (Sweden)

    NS Neki

    2016-05-01

    Full Text Available Antiplatelet agents are mainly used in the prevention and management of atherothrombotic complications. Dual antiplatelet therapy, combining aspirin and clopidogrel, is the standard care for patients having acute coronary syndromes or undergoing percutaneous coronary intervention according to the current ACC/AHA and ESC guidelines. But in spite of administration of dual antiplatelet therapy, some patients develop recurrent cardiovascular ischemic events especially stent thrombosis which is a serious clinical problem. Antiplatelet response to clopidogrel varies widely among patients based on ex vivo platelet function measurements. Clopidogrel is an effective inhibitor of platelet activation and aggregation due to its selective and irreversible blockade of the P2Y12 receptor. Patients who display little attenuation of platelet reactivity with clopidogrel therapy are labeled as low or nonresponders or clopidogrel resistant. The mechanism of clopidogrel resistance remains incompletely defined but there are certain clinical, cellular and genetic factors including polymorphisms responsible for therapeutic failure. Currently there is no standardized or widely accepted definition of clopidogrel resistance. The future may soon be realised in the routine measurement of platelet activity in the same way that blood pressure, cholesterol and blood sugar are followed to help guide the therapy, thus improving the care for millions of people. This review focuses on the methods used to identify patients with clopidogrel resistance, the underlying mechanisms, metabolism, clinical significance and current therapeutic strategies to overcome clopidogrel resistance. J Enam Med Col 2016; 6(1: 38-46

  9. Resistance to technological progress

    International Nuclear Information System (INIS)

    This article deals with the tolerance test the constitutional system (Basic Law) of the Federal Republic of Germany is currently put to as a consequence of the resistance to the power structure of this country, which is expressed in the name of protection and defense for the environment and world peace. This biopacifistic resistance movment, the author says, has nothing to do with the legal right to resist, as laid down in art. 20 (4) of the Basic Law. According to the author, this attitude is an offspring of fear of the hazards of technological progress, primarily of nuclear hazards. Practical resistance, the author states, is preceded by theoretical resistance in speech: De-legitimation of the democratic legality, of the parliamentary functions, of the supreme power of the government, and denial of the citizens duty of obedience. The author raises the question as to whether this attitude of disobedience on ecological grounds marks the onset of a fourth stage of development of the modern state, after we have passed through stages characterised by fear of civil war, of tyranny, and of social privation and suffering. There are no new ideas brought forward by the ecologically minded movement, the author says, for re-shaping our institutions or constitutional system. (HP)

  10. MSMA resistance studies.

    Science.gov (United States)

    Camper, N D; Keese, R J; Coker, P S

    2004-05-01

    Monosodium methanearsonate (MSMA)-resistant and -susceptible common cocklebur (Xanthium strumarium L.) and cotton (Gossypium hirsutum L.) were treated with MSMA. Plant parameters analyzed were: glutathione synthetase activity, selected amino acid (arginine, glutamic acid, alanine, citrulline, glutamine, and glutathione) content and arsenic content (MSMA, total arsenic, and arsonate). No reduction of arsenic from the parent pentavalent form present in MSMA to the trivalent form was detected. Arginine, glutamic acid, and glutamine content increased in tissue three days after MSMA treatment. Glutathione content decreased during the first three days after treatment; however, five days after treatment the resistant biotype of cocklebur and cotton had elevated glutathione levels (8-20 times greater, respectively). Glutathione Synthetase activity was higher in cotton than in either of the cocklebur biotypes; MSMA did not affect its activity in cotton or either cocklebur biotype. Resistant biotypes have a slightly higher activity than the susceptible biotype. Tolerance of cotton to MSMA may be related to glutathione synthetase activity and possibly to the presence of phytochelatins. Also, increased glutathione levels in the resistant biotype may implicate phytochelatin involvement in the resistance mechanism.

  11. Spore Resistance Properties.

    Science.gov (United States)

    Setlow, Peter

    2014-10-01

    Spores of various Bacillus and Clostridium species are among the most resistant life forms known. Since the spores of some species are causative agents of much food spoilage, food poisoning, and human disease, and the spores of Bacillus anthracis are a major bioweapon, there is much interest in the mechanisms of spore resistance and how these spores can be killed. This article will discuss the factors involved in spore resistance to agents such as wet and dry heat, desiccation, UV and γ-radiation, enzymes that hydrolyze bacterial cell walls, and a variety of toxic chemicals, including genotoxic agents, oxidizing agents, aldehydes, acid, and alkali. These resistance factors include the outer layers of the spore, such as the thick proteinaceous coat that detoxifies reactive chemicals; the relatively impermeable inner spore membrane that restricts access of toxic chemicals to the spore core containing the spore's DNA and most enzymes; the low water content and high level of dipicolinic acid in the spore core that protect core macromolecules from the effects of heat and desiccation; the saturation of spore DNA with a novel group of proteins that protect the DNA against heat, genotoxic chemicals, and radiation; and the repair of radiation damage to DNA when spores germinate and return to life. Despite their extreme resistance, spores can be killed, including by damage to DNA, crucial spore proteins, the spore's inner membrane, and one or more components of the spore germination apparatus.

  12. MSMA resistance studies.

    Science.gov (United States)

    Camper, N D; Keese, R J; Coker, P S

    2004-05-01

    Monosodium methanearsonate (MSMA)-resistant and -susceptible common cocklebur (Xanthium strumarium L.) and cotton (Gossypium hirsutum L.) were treated with MSMA. Plant parameters analyzed were: glutathione synthetase activity, selected amino acid (arginine, glutamic acid, alanine, citrulline, glutamine, and glutathione) content and arsenic content (MSMA, total arsenic, and arsonate). No reduction of arsenic from the parent pentavalent form present in MSMA to the trivalent form was detected. Arginine, glutamic acid, and glutamine content increased in tissue three days after MSMA treatment. Glutathione content decreased during the first three days after treatment; however, five days after treatment the resistant biotype of cocklebur and cotton had elevated glutathione levels (8-20 times greater, respectively). Glutathione Synthetase activity was higher in cotton than in either of the cocklebur biotypes; MSMA did not affect its activity in cotton or either cocklebur biotype. Resistant biotypes have a slightly higher activity than the susceptible biotype. Tolerance of cotton to MSMA may be related to glutathione synthetase activity and possibly to the presence of phytochelatins. Also, increased glutathione levels in the resistant biotype may implicate phytochelatin involvement in the resistance mechanism. PMID:15473645

  13. Correlation Analysis on the Relationship Between the Biological Characteristic of Ten Ornamental Tree Species and the Wind-resistance Ability in Hainan Island%海南10种园林乔木生物学特性与抗风性关联性分析

    Institute of Scientific and Technical Information of China (English)

    罗冠勇; 宋希强; 杨冬华; 张哲

    2013-01-01

    It is necessary to select ornamental tree species with stronger wind-resistance ability, especially in those areas with typhoon attacking frequently. Taking 10 common landscaping tree species in Danzhou , Hainan Province, graded and built data column depending on damaged scores of each species, carried the wind -resistance analysis depending on 4 indicators including tree height, diameter breast-high (DBH), under branch height and crown width, and took the Grey association analysis to explore the relations between the wind resistance and tree indicators after strong typhoon " Dawei" attack. The result showed that the rank of the relational extent between the tree indicators and wind resistance as follows: DBH>height>crown width>under branch height. For wind resistant ability of 10 species, Roystonea regia, Ficus microcarpa, Ficus microcarpa, Ciniuunomum camphora, Elaeis guineensis, Khara senegalenss and Delonix regia are strong, Mimusops elengi is medium, Bauhinia purpurea and Pterocarpus indie us are poor.%针对受强台风“达维”侵袭之后,海南省儋州地区常用的10种园林乔木,进行受损情况分级打分并以各树种的得分为参考数据列,以树高、胸径、枝下高和冠幅作为抗风性能分析评价指标,采用灰色关联分析方法对树种的自身指标因素与其抗风性能的关系进行分析.研究结果表明:树种的自身指标因素与其抗风性能的关联度大小依次为:胸径>树高>冠幅>枝下高;10种园林乔木的抗风能力,大王棕、黄葛榕、小叶榕、樟树、油棕、桃花心木和凤凰木较强,伊朗紫硬胶中等;羊蹄甲与印度紫檀较差.

  14. Exercise training in the management of patients with resistant hypertension

    Institute of Scientific and Technical Information of China (English)

    Fernando; Ribeiro; Rui; Costa; José; Mesquita-Bastos

    2015-01-01

    Hypertension is a very prevalent risk factor for cardiovascular disease. The prevalence of resistant hypertension, i.e., uncontrolled hypertension with 3 or more antihypertensive agents including 1 diuretic, is between 5% and 30% in the hypertensive population. The causes of resistant hypertension are multifactorial and include behavioral and biological factors, such as nonadherence to pharmacological treatment. All current treatment guidelines highlight the positive role of physical exercise as a non-pharmacological tool in the treatment of hypertension. This paper draws attention to the possible role of physical exercise as an adjunct non-pharmacological tool in the management of resistant hypertension. A few studies have investigated it, employing different methodologies, and taken together they have shown promising results. In summary, the available evidence suggests that aerobic physical exercise could be a valuable addition to the optimal pharmacological treatment of patients with resistant hypertension.

  15. Biology of Metastatic Renal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Michele Milella, Alessandra Felici

    2011-01-01

    Full Text Available In the past ten years we have made exceptional progresses in the understanding of RCC biology, particularly by recognizing the crucial pathogenetic role of activation of the HIF/VEGF and mTOR pathways. This has resulted in the successful clinical development of anti-angiogenic and mTOR-targeted drugs, which have profoundly impacted on the natural history of the disease and have improved the duration and quality of RCC patient lives. However, further improvements are still greatly needed: 1 even in patients who obtain striking clinical responses early in the course of treatment, disease will ultimately escape control and progress to a treatment-resistant state, leading to therapeutic failure; 2 prolonged disease control usually requires 'continuous' treatment, even across different treatment lines, making the impact of chronic, low-grade, toxicities on quality of life greater and precluding, for most patients, the possibility of experiencing 'drug-free holidays'; 3 although we have successfully identified classes of drugs (or molecular mechanisms of action that are effective in a substantial proportion of patients, we still fall short of molecular predictive factors that identify individual patients who will (or will not benefit from a specific intervention and still proceed on a trial-and-error basis, far from a truly 'personalized' therapeutic approach; 4 finally (and perhaps most importantly, even in the best case scenario, currently available treatments inevitably fail to definitively 'cure' metastatic RCC patients. In this review we briefly summarize recent developments in the understanding of the molecular pathogenesis of RCC, the development of resistance/escape mechanisms, the rationale for sequencing agents with different mechanisms of action, and the importance of host-related factors. Unraveling the complex mechanisms by which RCC shapes host microenvironment and immune response and therapeutic treatments, in turn, shape both cancer

  16. Transcriptome analysis of chlorantraniliprole resistance development in the diamondback moth Plutella xylostella.

    Directory of Open Access Journals (Sweden)

    Qingsheng Lin

    Full Text Available BACKGROUND: The diamondback moth Plutella xyllostella has developed a high level of resistance to the latest insecticide chlorantraniliprole. A better understanding of P. xylostella's resistance mechanism to chlorantraniliprole is needed to develop effective approaches for insecticide resistance management. PRINCIPAL FINDINGS: To provide a comprehensive insight into the resistance mechanisms of P. xylostella to chlorantraniliprole, transcriptome assembly and tag-based digital gene expression (DGE system were performed using Illumina HiSeq™ 2000. The transcriptome analysis of the susceptible strain (SS provided 45,231 unigenes (with the size ranging from 200 bp to 13,799 bp, which would be efficient for analyzing the differences in different chlorantraniliprole-resistant P. xylostella stains. DGE analysis indicated that a total of 1215 genes (189 up-regulated and 1026 down-regulated were gradient differentially expressed among the susceptible strain (SS and different chlorantraniliprole-resistant P. xylostella strains, including low-level resistance (GXA, moderate resistance (LZA and high resistance strains (HZA. A detailed analysis of gradient differentially expressed genes elucidated the existence of a phase-dependent divergence of biological investment at the molecular level. The genes related to insecticide resistance, such as P450, GST, the ryanodine receptor, and connectin, had different expression profiles in the different chlorantraniliprole-resistant DGE libraries, suggesting that the genes related to insecticide resistance are involved in P. xylostella resistance development against chlorantraniliprole. To confirm the results from the DGE, the expressional profiles of 4 genes related to insecticide resistance were further validated by qRT-PCR analysis. CONCLUSIONS: The obtained transcriptome information provides large gene resources available for further studying the resistance development of P. xylostella to pesticides. The DGE data

  17. Resistance to Insecticides in Insects

    OpenAIRE

    ÇAKIR, Şükran; Şengül YAMANEL

    2005-01-01

    In recent years, the frequent usage of insecticides in struggle aganist insects, has caused development of resistance to those chemicals in insects. The increase in dosage of insecticide used due to development of resistance in insects, causes important problems in terms of environment and human health. This study includes topics such as insecticides which are used frequently in insect struggle, insecticide resistant types, genetic changes posing resistance, enzymes of resistance and resistan...

  18. Heat-resistant materials

    CERN Document Server

    1997-01-01

    This handbook covers the complete spectrum of technology dealing with heat-resistant materials, including high-temperature characteristics, effects of processing and microstructure on high-temperature properties, materials selection guidelines for industrial applications, and life-assessment methods. Also included is information on comparative properties that allows the ranking of alloy performance, effects of processing and microstructure on high-temperature properties, high-temperature oxidation and corrosion-resistant coatings for superalloys, and design guidelines for applications involving creep and/or oxidation. Contents: General introduction (high-temperature materials characteristics, and mechanical and corrosion properties, and industrial applications); Properties of Ferrous Heat-Resistant Alloys (carbon, alloy, and stainless steels; alloy cast irons; and high alloy cast steels); Properties of superalloys (metallurgy and processing, mechanical and corrosion properties, degradation, and protective coa...

  19. Insecticide Resistance in Fleas.

    Science.gov (United States)

    Rust, Michael K

    2016-01-01

    Fleas are the major ectoparasite of cats, dogs, and rodents worldwide and potential vectors of animal diseases. In the past two decades the majority of new control treatments have been either topically applied or orally administered to the host. Most reports concerning the development of insecticide resistance deal with the cat flea, Ctenocephalides felis felis. Historically, insecticide resistance has developed to many of the insecticides used to control fleas in the environment including carbamates, organophosphates, and pyrethroids. Product failures have been reported with some of the new topical treatments, but actual resistance has not yet been demonstrated. Failures have often been attributed to operational factors such as failure to adequately treat the pet and follow label directions. With the addition of so many new chemistries additional monitoring of flea populations is needed. PMID:26999217

  20. Pyrethroid resistance in mosquitoes

    Institute of Scientific and Technical Information of China (English)

    NANNAN LIU; QIANG XU; FANG ZHU; LEE ZHANG

    2006-01-01

    Repeated blood feedings throughout their life span have made mosquitoes ideal transmitters of a wide variety of disease agents. Vector control is a very important part of the current global strategy for the control of mosquito-associated diseases and insecticide application is the most important component in this effort. Pyrethroids, which account for 25% of the world insecticide market, are currently the most widely used insecticides for the indoor control of mosquitoes and are the only chemical recommended for the treatment of mosquito nets, the main tool for preventing malaria in Africa. However, mosquito-borne diseases are now resurgent, largely because of insecticide resistance that has developed in mosquito vectors and the anti-parasite drug resistance of parasites. This paper reviews our current knowledge of the molecular mechanisms governing metabolic detoxification and the development of target site insensitivity that leads to pyrethroid resistance in mosquitoes.

  1. Microfluidic Technologies for Synthetic Biology

    Directory of Open Access Journals (Sweden)

    Sung Kuk Lee

    2011-06-01

    Full Text Available Microfluidic technologies have shown powerful abilities for reducing cost, time, and labor, and at the same time, for increasing accuracy, throughput, and performance in the analysis of biological and biochemical samples compared with the conventional, macroscale instruments. Synthetic biology is an emerging field of biology and has drawn much attraction due to its potential to create novel, functional biological parts and systems for special purposes. Since it is believed that the development of synthetic biology can be accelerated through the use of microfluidic technology, in this review work we focus our discussion on the latest microfluidic technologies that can provide unprecedented means in synthetic biology for dynamic profiling of gene expression/regulation with high resolution, highly sensitive on-chip and off-chip detection of metabolites, and whole-cell analysis.

  2. Quantum Effects in Biological Systems

    CERN Document Server

    2016-01-01

    Since the last decade the study of quantum mechanical phenomena in biological systems has become a vibrant field of research. Initially sparked by evidence of quantum effects in energy transport that is instrumental for photosynthesis, quantum biology asks the question of how methods and models from quantum theory can help us to understand fundamental mechanisms in living organisms. This approach entails a paradigm change challenging the related disciplines: The successful framework of quantum theory is taken out of its low-temperature, microscopic regimes and applied to hot and dense macroscopic environments, thereby extending the toolbox of biology and biochemistry at the same time. The Quantum Effects in Biological Systems conference is a platform for researchers from biology, chemistry and physics to present and discuss the latest developments in the field of quantum biology. After meetings in Lisbon (2009), Harvard (2010), Ulm (2011), Berkeley (2012), Vienna (2013), Singapore (2014) and Florence (2015),...

  3. Semiconductor Quantum Rods as Single Molecule FluorescentBiological Labels

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Aihua; Gu, Weiwei; Boussert, Benjamine; Koski, Kristie; Gerion, Daniele; Manna, Liberato; Le Gros, Mark; Larabell, Carolyn; Alivisatos, A. Paul

    2006-05-29

    In recent years, semiconductor quantum dots have beenapplied with great advantage in a wide range of biological imagingapplications. The continuing developments in the synthesis of nanoscalematerials and specifically in the area of colloidal semiconductornanocrystals have created an opportunity to generate a next generation ofbiological labels with complementary or in some cases enhanced propertiescompared to colloidal quantum dots. In this paper, we report thedevelopment of rod shaped semiconductor nanocrystals (quantum rods) asnew fluorescent biological labels. We have engineered biocompatiblequantum rods by surface silanization and have applied them fornon-specific cell tracking as well as specific cellular targeting. Theproperties of quantum rods as demonstrated here are enhanced sensitivityand greater resistance for degradation as compared to quantum dots.Quantum rods have many potential applications as biological labels insituations where their properties offer advantages over quantumdots.

  4. Consequence etiology and biological teleology in Aristotle and Darwin.

    Science.gov (United States)

    Depew, David J

    2008-12-01

    Aristotle's biological teleology is rooted in an epigenetic account of reproduction. As such, it is best interpreted by consequence etiology. I support this claim by citing the capacity of consequence etiology's key distinctions to explain Aristotle's opposition to Empedocles. There are implications for the relation between ancient and modern biology. The analysis reveals that in an important respect Darwin's account of adaptation is closer to Aristotle's than to Empedocles's. They both rely on consequence etiological considerations to evade attributing the purposiveness of organisms to chance. Two implications follow: (l) Darwinian explanations of adaptation are as teleological as Aristotle's, albeit differently; and (2) these differences show how deeply resistant Aristotle's version of biological teleology is to descent from a common ancestor. PMID:19026970

  5. Anti-tick biological control agents: assessment and future perspectives

    Science.gov (United States)

    Samish, M., H.; Ginsberg, H.S.; Glazer, I.

    2008-01-01

    Widespread and increasing resistance to most available acaracides threatens both global livestock industries and public health. This necessitates better understanding of ticks and the diseases they transmit in the development of new control strategies. Ticks: Biology, Disease and Control is written by an international collection of experts and covers in-depth information on aspects of the biology of the ticks themselves, various veterinary and medical tick-borne pathogens, and aspects of traditional and potential new control methods. A valuable resource for graduate students, academic researchers and professionals, the book covers the whole gamut of ticks and tick-borne diseases from microsatellites to satellite imagery and from exploiting tick saliva for therapeutic drugs to developing drugs to control tick populations. It encompasses the variety of interconnected fields impinging on the economically important and biologically fascinating phenomenon of ticks, the diseases they transmit and methods of their control.

  6. 2007 Microbial Population Biology (July 22-26, 2007)

    Energy Technology Data Exchange (ETDEWEB)

    Anthony M. Dean

    2008-04-01

    Microbial Population Biology covers a diverse range of cutting edge issues in the microbial sciences and beyond. Firmly founded in evolutionary biology and with a strongly integrative approach, past meetings have covered topics ranging from the dynamics and genetics of adaptation to the evolution of mutation rate, community ecology, evolutionary genomics, altruism, and epidemiology. This meeting is never dull: some of the most significant and contentious issues in biology have been thrashed out here. We anticipate the 2007 meeting being no exception. The final form of the 2007 meeting is yet to be decided, but the following topics are likely to be included: evolutionary emergence of infectious disease and antibiotic resistance, genetic architecture and implications for the evolution of microbial populations, ageing in bacteria, biogeography, evolution of symbioses, the role of microbes in ecosystem function, and ecological genomics.

  7. Research of radiation-resistant microbial organisms

    International Nuclear Information System (INIS)

    Many extremophiles including radiation-resistant bacteria Deinococcus radiodurans have special characteristics such as novel enzymes and physiological active substances different from known biological materials and are being in the spotlight of biotechnology science. In this research, basic technologies for the production of new genetic resources and microbial strains by a series of studies in radiation-resistant microbial organisms were investigated and developed. Mechanisms required for radiation-resistant in Deinococcus radiodurans were partly defined by analyzing the function of dinB, pprI, recG, DRA0279, pprM, and two-component signal transduction systems. To apply genetic resource and functional materials from Deinococcus species, omics analysis in response to cadmium, construction of macroscopic biosensor, and characterization of carotenoids and chaperon protein were performed. Additionally, potential use of D. geothermalis in monosaccharide production from non-biodegradable plant materials was evaluated. Novel radiation resistant yeasts and bacteria were isolated and identified from environmental samples to obtain microbial and genomic resources. An optimal radiation mutant breeding method was set up for efficient and rapid isolation of target microbial mutants. Furthermore, an efficient ethanol producing mutant strain with high production yield and productivity was constructed using the breeding method in collaboration with Korea Research Institute of Bioscience and Biotechnology. Three Deinococcal bioindicators for radiation dosage confirmation after radiation sterilization process were developed. These results provide a comprehensive information for novel functional genetic elements, enzymes, and physiological active substances production or application. Eventually, industrial microbial cell factories based on radiation resistant microbial genomes can be developed and the technologies can be diffused to bioindustry continuously by this project

  8. Research of radiation-resistant microbial organisms

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dongho; Lim, Sangyong; Joe, Minho; Park, Haejoon; Song, Hyunpa; Im, Seunghun; Kim, Haram; Kim, Whajung; Choi, Jinsu; Park, Jongchun

    2012-01-15

    Many extremophiles including radiation-resistant bacteria Deinococcus radiodurans have special characteristics such as novel enzymes and physiological active substances different from known biological materials and are being in the spotlight of biotechnology science. In this research, basic technologies for the production of new genetic resources and microbial strains by a series of studies in radiation-resistant microbial organisms were investigated and developed. Mechanisms required for radiation-resistant in Deinococcus radiodurans were partly defined by analyzing the function of dinB, pprI, recG, DRA{sub 0}279, pprM, and two-component signal transduction systems. To apply genetic resource and functional materials from Deinococcus species, omics analysis in response to cadmium, construction of macroscopic biosensor, and characterization of carotenoids and chaperon protein were performed. Additionally, potential use of D. geothermalis in monosaccharide production from non-biodegradable plant materials was evaluated. Novel radiation resistant yeasts and bacteria were isolated and identified from environmental samples to obtain microbial and genomic resources. An optimal radiation mutant breeding method was set up for efficient and rapid isolation of target microbial mutants. Furthermore, an efficient ethanol producing mutant strain with high production yield and productivity was constructed using the breeding method in collaboration with Korea Research Institute of Bioscience and Biotechnology. Three Deinococcal bioindicators for radiation dosage confirmation after radiation sterilization process were developed. These results provide a comprehensive information for novel functional genetic elements, enzymes, and physiological active substances production or application. Eventually, industrial microbial cell factories based on radiation resistant microbial genomes can be developed and the technologies can be diffused to bioindustry continuously by this project.

  9. Computational Biology: A Programming Perspective

    DEFF Research Database (Denmark)

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

    2011-01-01

    identify some strengths and shortcomings from a programming perspective. To show concretely what one could see as programming in biocomputing, we outline (from recent work) a computation model and a small programming language that are biologically more plausible than existing silicon-inspired models....... Whether or not the model is biologically plausible in an absolute sense, we believe it sets a standard for a biological device that can be both universal and programmable....

  10. Telemetry System of Biological Parameters

    OpenAIRE

    2005-01-01

    The mobile telemetry system of biological parameters serves for reading and wireless data transfer of measured values of selected biological parameters to an outlying computer. It concerns basically long time monitoring of vital function of car pilot.The goal of this projects is to propose mobile telemetry system for reading, wireless transfer and processing of biological parameters of car pilot during physical and psychical stress. It has to be made with respect to minimal consum...

  11. Advances and Developing Tendency of Water Use Efficiency in Plant Biology

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhao-bo; TANG Jiao-wen; ZHANG Fu

    2009-01-01

    Biological water saving is one of the major fields of water saving agriculture in the future and has an enormous potential in agricultural production. In this paper, the necessity and urgency of developing high water use efficiency in plant biology were dissertated firstly, and the research progresses at home and abroad were reviewed as following aspects: mechanisms of drought resistance and high water use efficiency, criterions for identifying and evaluating drought resistance and water use efficiency, genetic improvement for drought resistance and water use efficiency, water saving irrigation technology based on the physiological regulation and control in crop plants. Major problems in the research field at present were put forward, and development tendency of water use efficiency in plant biology in the future were also discussed.

  12. Relations between Intuitive Biological Thinking and Biological Misconceptions in Biology Majors and Nonmajors

    Science.gov (United States)

    Coley, John D.; Tanner, Kimberly

    2015-01-01

    Research and theory development in cognitive psychology and science education research remain largely isolated. Biology education researchers have documented persistent scientifically inaccurate ideas, often termed misconceptions, among biology students across biological domains. In parallel, cognitive and developmental psychologists have described intuitive conceptual systems—teleological, essentialist, and anthropocentric thinking—that humans use to reason about biology. We hypothesize that seemingly unrelated biological misconceptions may have common origins in these intuitive ways of knowing, termed cognitive construals. We presented 137 undergraduate biology majors and nonmajors with six biological misconceptions. They indicated their agreement with each statement, and explained their rationale for their response. Results indicate frequent agreement with misconceptions, and frequent use of construal-based reasoning among both biology majors and nonmajors in their written explanations. Moreover, results also show associations between specific construals and the misconceptions hypothesized to arise from those construals. Strikingly, such associations were stronger among biology majors than nonmajors. These results demonstrate important linkages between intuitive ways of thinking and misconceptions in discipline-based reasoning, and raise questions about the origins, persistence, and generality of relations between intuitive reasoning and biological misconceptions. PMID:25713093

  13. Corrosion resistant amorphous alloys

    International Nuclear Information System (INIS)

    A review of publication data on corrosion resistance of amorphous alloys and the methods of amorphization of surface layers of massive materials (laser treatment, iron implantation, detonation-gas spraying, cathode and ion sputtering, electrodeposition) was made. A study was made on corrosion properties of Fe66Cr11B10Si4 alloy in cast state and after laser irradiation, rendering the surface amorphous as well as the samples of Arenco iron and steel 20 with ion-plasma coatings of Fe-Cr-Ni-Ti alloy. It was established that amorphous coatings posses much higher corrosion resistance as compared to crystalline alloys on the same base

  14. Resisting religious coercive control.

    Science.gov (United States)

    Sharp, Shane

    2014-12-01

    Religious coercive control refers to the use of religious beliefs and doctrine as means to coercively control intimate partners. Scholars have shown that some abusive partners use the Christian doctrine of submission as a means of religious coercive control. I explore how victims who experience the doctrine of submission qua religious coercive control actively resist it. I argue that victims' successful resistance of the doctrine is contingent on their religious capital-that is, the knowledge and mastery that people have of a particular religious culture-and interpretive confidence-that is, people's subjective confidence in their interpretations of religious culture-related to the doctrine. PMID:25398370

  15. Kinetically Controlled Drug Resistance

    DEFF Research Database (Denmark)

    Sun, Xin E.; Hansen, Bjarne Gram; Hedstrom, Lizbeth

    2011-01-01

    The filamentous fungus Penicillium brevicompactum produces the immunosuppressive drug mycophenolic acid (MPA), which is a potent inhibitor of eukaryotic IMP dehydrogenases (IMPDHs). IMPDH catalyzes the conversion of IMP to XMP via a covalent enzyme intermediate, E-XMP*; MPA inhibits by trapping E...... of resistance is not apparent. Here, we show that, unlike MPA-sensitive IMPDHs, formation of E-XMP* is rate-limiting for both PbIMPDH-A and PbIMPDH-B. Therefore, MPA resistance derives from the failure to accumulate the drug-sensitive intermediate....

  16. Low level deltamethrin resistance in ticks from cattle of Kerala, a south Indian state.

    Science.gov (United States)

    Jyothimol, G; Ravindran, R; Juliet, S; Ajithkumar, K G; Suresh, N N; Vimalkumar, M B; Lenka, D R; Varghese, S; Ghosh, Srikanta

    2014-08-29

    The deltamethrin resistance status in Rhipicephalus (Boophilus) annulatus and R. (B.) microplus ticks collected from cattle of five organized farms of Kerala, south India was evaluated. Resistance was characterized using biological (larval packet test), biochemical (esterase enzyme activity assay) and molecular tools (PCR amplification and sequencing of deltamethrin resistance-associated genes). Characterization of field isolates revealed level I resistance in ticks collected from four out of five farms. Elevated level of α/β esterase activity was not recorded in isolates showing level I resistance. Previously reported point mutations in the carboxyl esterase (G1120A) and sodium channel (T2134A and C190A) genes were not observed in any of the field isolates. The present study showed a low level (level I) resistance is developed in the most economically important ticks infesting cattle of this state and it cautions the development of large scale resistance in future. PMID:24877788

  17. Generalized effective medium resistivity model for low resistivity reservoir

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    With the advancement in oil exploration,producible oil and gas are being found in low resistivity reservoirs,which may otherwise be erroneously thought as water zones from their resistivity.However,the evaluation of low resistivity reservoirs remains difficult from log interpretation.Since low resistivity in hydrocarbon bearing sands can be caused by dispersed clay,laminated shale,conductive matrix grains,microscopic capillary pores and high saline water,a new resistivity model is required for more accurate hydrocarbon saturation prediction for low resistivity formations.Herein,a generalized effective medium resistivity model has been proposed for low resistivity reservoirs,based on experimental measurements on artificial low resistivity shaly sand samples,symmetrical anisotropic effective medium theory for resistivity interpretations,and geneses and conductance mechanisms of low resistivity reservoirs.By analyzing effects of some factors on the proposed model,we show theoretically the model can describe conductance mechanisms of low resistivity reservoirs with five geneses.Also,shale distribution largely affects water saturation predicted by the model.Resistivity index decreases as fraction and conductivity of laminated shale,or fraction of dispersed clay,or conductivity of rock matrix grains increases.Resistivity index decreases as matrix percolation exponent,or percolation rate of capillary bound water increases,and as percolation exponent of capillary bound water,or matrix percolation rate,or free water percolation rate decreases.Rock sample data from low resistivity reservoirs with different geneses and interpretation results for log data show that the proposed model can be applied in low resistivity reservoirs containing high salinity water,dispersed clay,microscopic capillary pores,laminated shale and conductive matrix grains,and thus is considered as a generalized resistivity model for low resistivity reservoir evaluation.

  18. Generalized effective medium resistivity model for low resistivity reservoir

    Institute of Scientific and Technical Information of China (English)

    SONG YanJie; TANG XiaoMin

    2008-01-01

    With the advancement in oil exploration, producible oil and gas are being found in low resistivity reservoirs, which may otherwise be erroneously thought as water zones from their resistivity. However,the evaluation of low resistivity reservoirs remains difficult from log interpretation. Since low resistivity in hydrocarbon bearing sands can be caused by dispersed clay, laminated shale, conductive matrix grains, microscopic capillary pores and high saline water, a new resistivity model is required for more accurate hydrocarbon saturation prediction for low resistivity formations. Herein, a generalized effective medium resistivity model has been proposed for low resistivity reservoirs, based on experimental measurements on artificial low resistivity shaly sand samples, symmetrical anisotropic effective medium theory for resistivity interpretations, and geneses and conductance mechanisms of low resistivity reservoirs. By analyzing effects of some factors on the proposed model, we show theoretically the model can describe conductance mechanisms of low resistivity reservoirs with five geneses. Also,shale distribution largely affects water saturation predicted by the model. Resistivity index decreases as fraction and conductivity of laminated shale, or fraction of dispersed clay, or conductivity of rock matrix grains increases. Resistivity index decreases as matrix percolation exponent, or percolation rate of capillary bound water increases, and as percolation exponent of capillary bound water, or matrix percolation rate, or free water percolation rate decreases. Rock sample data from low resistivity reservoirs with different geneses and interpretation results for log data show that the proposed model can be applied in low resistivity reservoirs containing high salinity water, dispersed clay, microscopic capillary pores, laminated shale and conductive matrix grains, and thus is considered as a generalized resistivity model for low resistivity reservoir evaluation.

  19. The ontology of biological sequences

    Directory of Open Access Journals (Sweden)

    Kelso Janet

    2009-11-01

    Full Text Available Abstract Background Biological sequences play a major role in molecular and computational biology. They are studied as information-bearing entities that make up DNA, RNA or proteins. The Sequence Ontology, which is part of the OBO Foundry, contains descriptions and definitions of sequences and their properties. Yet the most basic question about sequences remains unanswered: what kind of entity is a biological sequence? An answer to this question benefits formal ontologies that use the notion of biological sequences and analyses in computational biology alike. Results We provide both an ontological analysis of biological sequences and a formal representation that can be used in knowledge-based applications and other ontologies. We distinguish three distinct kinds of entities that can be referred to as "biological sequence": chains of molecules, syntactic representations such as those in biological databases, and the abstract information-bearing entities. For use in knowledge-based applications and inclusion in biomedical ontologies, we implemented the developed axiom system for use in automated theorem proving. Conclusion Axioms are necessary to achieve the main goal of ontologies: to formally specify the meaning of terms used within a domain. The axiom system for the ontology of biological sequences is the first elaborate axiom system for an OBO Foundry ontology and can serve as starting point for the development of more formal ontologies and ultimately of knowledge-based applications.

  20. Biological and medical sensor technologies

    CERN Document Server

    Iniewski, Krzysztof

    2012-01-01

    Biological and Medical Sensor Technologies presents contributions from top experts who explore the development and implementation of sensors for various applications used in medicine and biology. Edited by a pioneer in the area of advanced semiconductor materials, the book is divided into two sections. The first part covers sensors for biological applications. Topics include: Advanced sensing and communication in the biological world DNA-derivative architectures for long-wavelength bio-sensing Label-free silicon photonics Quartz crystal microbalance-based biosensors Lab-on-chip technologies fo

  1. Telemetry System of Biological Parameters

    Directory of Open Access Journals (Sweden)

    Jan Spisak

    2005-01-01

    Full Text Available The mobile telemetry system of biological parameters serves for reading and wireless data transfer of measured values of selected biological parameters to an outlying computer. It concerns basically long time monitoring of vital function of car pilot.The goal of this projects is to propose mobile telemetry system for reading, wireless transfer and processing of biological parameters of car pilot during physical and psychical stress. It has to be made with respect to minimal consumption, weight and maximal device mobility. This system has to eliminate signal noise, which is created by biological artifacts and disturbances during the data transfer.

  2. Ethical Issues in Synthetic Biology

    OpenAIRE

    Heavey, Patrick Joseph

    2013-01-01

    Synthetic biology has been defined as: “the design and construction of new biological parts, devices, and systems, and the re-design of existing, natural biological systems for useful purposes” (syntheticbiology.org). The convergence of scientific fields such as molecular biology, computer science and others have rendered it a natural progression, based on existing knowledge.The fact that humanity has reached a stage of development where it seems feasible to “create” life, or design it to a h...

  3. Nanopreparations to overcome multidrug resistance in cancer.

    Science.gov (United States)

    Patel, Niravkumar R; Pattni, Bhushan S; Abouzeid, Abraham H; Torchilin, Vladimir P

    2013-11-01

    Multidrug resistance is the most widely exploited phenomenon by which cancer eludes chemotherapy. Broad variety of factors, ranging from the cellular ones, such as over-expression of efflux transporters, defective apoptotic machineries, and altered molecular targets, to the physiological factors such as higher interstitial fluid pressure, low extracellular pH, and formation of irregular tumor vasculature are responsible for multidrug resistance. A combination of various undesirable factors associated with biological surroundings together with poor solubility and instability of many potential therapeutic small & large molecules within the biological systems and systemic toxicity of chemotherapeutic agents has necessitated the need for nano-preparations to optimize drug delivery. The physiology of solid tumors presents numerous challenges for successful therapy. However, it also offers unique opportunities for the use of nanotechnology. Nanoparticles, up to 400 nm in size, have shown great promise for carrying, protecting and delivering potential therapeutic molecules with diverse physiological properties. In this review, various factors responsible for the MDR and the use of nanotechnology to overcome the MDR, the use of spheroid culture as well as the current technique of producing microtumor tissues in vitro are discussed in detail. PMID:23973912

  4. The role of miRNA regulation in cancer progression and drug resistance

    DEFF Research Database (Denmark)

    Joshi, Tejal

    RNAs in the context of cancer biology, drug resistance and disease progression. The first project described in Chapter 6 addresses the problem of tamoxifen resistance, an anti-estrogen drug that is generally highly effective in the treatment of ER-positive breast cancers. The underlying molecular mechanisms......This PhD thesis presents the work carried out at Center for Biological Sequence Analysis, Technical University of Denmark. The projects presented in this thesis are a purely bioinformatic in nature. Included in this thesis are the two projects that focus on the gene regulatory events mediated by mi...... for the acquired resistance to tamoxifen are not very well understood. Therefore, with the aid of miRNA and gene expression profiles for MCF7/S0.5 (tamoxifen sensitive) and three MCF7/S0.5 derived tamoxifen resistant cell lines, we obtained several miRNA-mediated regulatory events in the tamoxifen resistant cell...

  5. Biologically Inspired Organic Light-Emitting Diodes.

    Science.gov (United States)

    Kim, Jae-Jun; Lee, Jaeho; Yang, Sung-Pyo; Kim, Ha Gon; Kweon, Hee-Seok; Yoo, Seunghyup; Jeong, Ki-Hun

    2016-05-11

    Many animal species employ highly conspicuous traits as courtship signals for successful mating. Fireflies utilize their bioluminescent light as visual courtship signals. In addition to efficient bioluminescent light emission, the structural components of the firefly lantern also contribute to the enhancement of conspicuous optical signaling. Recently, these firefly lantern ultrastructures have attracted much interest and inspired highly efficient light management approaches. Here we report on the unique optical function of the hierarchical ultrastructures found in a firefly (Pyrocoelia rufa) and their biological inspiration of highly efficient organic light-emitting diode (OLED) applications. The hierarchical structures are comprised of longitudinal nanostructures and asymmetric microstructures, which were successfully replicated using geometry-guided resist reflow, replica molding, and polydimethylsiloxane (PDMS) oxidation. The external quantum efficiency (EQE) of the bioinspired OLEDs was enhanced by up to 61%. The bioinspired OLEDs clearly showed side-enhanced super-Lambertian emission with a wide-viewing angle. The highly efficient light extraction and wide-angle illumination suggest how the hierarchical structures likely improve the recognition of firefly optical courtship signals over a wide-angle range. At the same time, the biologically inspired designs provide a new paradigm for designing functional optical surfaces for lighting or display applications. PMID:27014918

  6. The mechanics of soft biological composites.

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Thao D. (Sandia National Laboratories, Livermore, CA); Grazier, John Mark; Boyce, Brad Lee; Jones, Reese E. (Sandia National Laboratories, Livermore, CA)

    2007-10-01

    Biological tissues are uniquely structured materials with technologically appealing properties. Soft tissues such as skin, are constructed from a composite of strong fibrils and fluid-like matrix components. This was the first coordinated experimental/modeling project at Sandia or in the open literature to consider the mechanics of micromechanically-based anisotropy and viscoelasticity of soft biological tissues. We have exploited and applied Sandia's expertise in experimentation and mechanics modeling to better elucidate the behavior of collagen fibril-reinforced soft tissues. The purpose of this project was to provide a detailed understanding of the deformation of ocular tissues, specifically the highly structured skin-like tissue in the cornea. This discovery improved our knowledge of soft/complex materials testing and modeling. It also provided insight into the way that cornea tissue is bio-engineered such that under physiologically-relevant conditions it has a unique set of properties which enhance functionality. These results also provide insight into how non-physiologic loading conditions, such as corrective surgeries, may push the cornea outside of its natural design window, resulting in unexpected non-linear responses. Furthermore, this project created a clearer understanding of the mechanics of soft tissues that could lead to bio-inspired materials, such as highly supple and impact resistant body armor, and improve our design of human-machine interfaces, such as micro-electrical-mechanical (MEMS) based prosthetics.

  7. A Free Energy Principle for Biological Systems

    Directory of Open Access Journals (Sweden)

    Friston Karl

    2012-10-01

    Full Text Available This paper describes a free energy principle that tries to explain the ability of biological systems to resist a natural tendency to disorder. It appeals to circular causality of the sort found in synergetic formulations of self-organization (e.g., the slaving principle and models of coupled dynamical systems, using nonlinear Fokker Planck equations. Here, circular causality is induced by separating the states of a random dynamical system into external and internal states, where external states are subject to random fluctuations and internal states are not. This reduces the problem to finding some (deterministic dynamics of the internal states that ensure the system visits a limited number of external states; in other words, the measure of its (random attracting set, or the Shannon entropy of the external states is small. We motivate a solution using a principle of least action based on variational free energy (from statistical physics and establish the conditions under which it is formally equivalent to the information bottleneck method. This approach has proved useful in understanding the functional architecture of the brain. The generality of variational free energy minimisation and corresponding information theoretic formulations may speak to interesting applications beyond the neurosciences; e.g., in molecular or evolutionary biology.

  8. Howard Brenner's Legacy for Biological Transport Processes

    Science.gov (United States)

    Nitsche, Johannes

    2014-11-01

    This talk discusses the manner in which Howard Brenner's theoretical contributions have had, and long will have, strong and direct impact on the understanding of transport processes occurring in biological systems. His early work on low Reynolds number resistance/mobility coefficients of arbitrarily shaped particles, and particles near walls and in pores, is an essential component of models of hindered diffusion through many types of membranes and tissues, and convective transport in microfluidic diagnostic systems. His seminal contributions to macrotransport (coarse-graining, homogenization) theory presaged the growing discipline of multiscale modeling. For biological systems they represent the key to infusing diffusion models of a wide variety of tissues with a sound basis in their microscopic structure and properties, often over a hierarchy of scales. Both scientific currents are illustrated within the concrete context of diffusion models of drug/chemical diffusion through the skin. This area of theory, which is key to transdermal drug development and risk assessment of chemical exposure, has benefitted very directly from Brenner's contributions. In this as in other areas, Brenner's physicochemical insight, mathematical virtuosity, drive for fully justified analysis free of ad hoc assumptions, quest for generality, and impeccable exposition, have consistently elevated the level of theoretical understanding and presentation. We close with anecdotes showing how his personal qualities and warmth helped to impart high standards of rigor to generations of grateful research students. Authors are Johannes M. Nitsche, Ludwig C. Nitsche and Gerald B. Kasting.

  9. Transport and transformation of genetic information in the critical zone: The case of antibiotic resistance genes

    Science.gov (United States)

    Zhu, Y. G.

    2015-12-01

    In addition to material and energy flows, the dynamics and functions of the Earth's critical zone are intensively mediated by biological actions performed by diverse organisms. These biological actions are modulated by the expression of functional genes and their translation into enzymes that catalyze geochemical reactions, such as nutrient turnover and pollutant biodegradation. Although geobiology, as an interdisciplinary research area, is playing and vital role in linking biological and geochemical processes at different temporal and spatial scales, the distribution and transport of functional genes have rarely been investigated from the Earth's critical zone perspectives. To illustrate the framework of studies on the transport and transformation of genetic information in the critical zone, antibiotic resistance is taken as an example. Antibiotic resistance genes are considered as a group of emerging contaminants, and their emergence and spread within the critical zone on one hand are induced by anthropogenic activities, and on other hand are threatening human health worldwide. The transport and transformation of antibiotic resistance genes are controlled by both horizontal gene transfer between bacterial cells and the movement of bacteria harboring antibiotic resistance genes. In this paper, the fate and behavior of antibiotic resistance genes will be discussed in the following aspects: 1) general overview of environmental antibiotic resistance; 2) high through quantification of the resistome in various environmental media; 3) pathways of resistance gene flow within the critical zone; and 4) potential strategies in mitigating antibiotic resistance, particularly from the critical zone perspectives.

  10. Crystallogenesis of biological macromolecules. Biological, microgravity and other physicochemical aspects

    NARCIS (Netherlands)

    Giege, R; Drenth, J; Ducruix, A; McPherson, A; Saenger, W

    1995-01-01

    After an historical introduction and justification of the importance of proteins (as well as other macromolecules or macromolecular assemblies of biological origin) in modern biology but also in physics, this review presents the state of the field of macromolecular crystallogenesis. The basic questi

  11. Rotating Biological Contractors (RBC's). Instructor's Guide. Biological Treatment Process Control.

    Science.gov (United States)

    Zickefoose, Charles S.

    This two-lesson unit on rotating biological contactors (RBC's) is designed to be used with students who have had some experience in wastewater treatment and a basic understanding of biological treatment. The first lesson provides information on the concepts and components of RBC treatment systems. The second lesson focuses on design operation and…

  12. Exploring Visuomotor Priming Following Biological and Non-Biological Stimuli

    Science.gov (United States)

    Gowen, E.; Bradshaw, C.; Galpin, A.; Lawrence, A.; Poliakoff, E.

    2010-01-01

    Observation of human actions influences the observer's own motor system, termed visuomotor priming, and is believed to be caused by automatic activation of mirror neurons. Evidence suggests that priming effects are larger for biological (human) as opposed to non-biological (object) stimuli and enhanced when viewing stimuli in mirror compared to…

  13. Quantitative biology: where modern biology meets physical sciences.

    Science.gov (United States)

    Shekhar, Shashank; Zhu, Lian; Mazutis, Linas; Sgro, Allyson E; Fai, Thomas G; Podolski, Marija

    2014-11-01

    Quantitative methods and approaches have been playing an increasingly important role in cell biology in recent years. They involve making accurate measurements to test a predefined hypothesis in order to compare experimental data with predictions generated by theoretical models, an approach that has benefited physicists for decades. Building quantitative models in experimental biology not only has led to discoveries of counterintuitive phenomena but has also opened up novel research directions. To make the biological sciences more quantitative, we believe a two-pronged approach needs to be taken. First, graduate training needs to be revamped to ensure biology students are adequately trained in physical and mathematical sciences and vice versa. Second, students of both the biological and the physical sciences need to be provided adequate opportunities for hands-on engagement with the methods and approaches necessary to be able to work at the intersection of the biological and physical sciences. We present the annual Physiology Course organized at the Marine Biological Laboratory (Woods Hole, MA) as a case study for a hands-on training program that gives young scientists the opportunity not only to acquire the tools of quantitative biology but also to develop the necessary thought processes that will enable them to bridge the gap between these disciplines.

  14. "Protected biological control"- Biological pest management in the greenhouse industry

    NARCIS (Netherlands)

    Pilkington, L.J.; Messelink, G.J.; Lenteren, van J.C.; Mottee, Le K.

    2010-01-01

    This paper briefly describes the foundations and characteristics of biological control in protected cropping and what drivers are behind adoption of this management system within this industry. Examining a brief history of biological control in greenhouses and what makes it a successful management s

  15. Flotation of Biological Materials

    Directory of Open Access Journals (Sweden)

    George Z. Kyzas

    2014-03-01

    Full Text Available Flotation constitutes a gravity separation process, which originated from the minerals processing field. However, it has, nowadays, found several other applications, as for example in the wastewater treatment field. Concerning the necessary bubble generation method, typically dispersed-air or dissolved-air flotation was mainly used. Various types of biological materials were tested and floated efficiently, such as bacteria, fungi, yeasts, activated sludge, grape stalks, etc. Innovative processes have been studied in our Laboratory, particularly for metal ions removal, involving the initial abstraction of heavy metal ions onto a sorbent (including a biosorbent: in the first, the application of a flotation stage followed for the efficient downstream separation of metal-laden particles. The ability of microorganisms to remove metal ions from dilute aqueous solutions (as most wastewaters are is a well-known property. The second separation process, also applied effectively, was a new hybrid cell of microfiltration combined with flotation. Sustainability in this field and its significance for the chemical and process industry is commented.

  16. Analog synthetic biology.

    Science.gov (United States)

    Sarpeshkar, R

    2014-03-28

    We analyse the pros and cons of analog versus digital computation in living cells. Our analysis is based on fundamental laws of noise in gene and protein expression, which set limits on the energy, time, space, molecular count and part-count resources needed to compute at a given level of precision. We conclude that analog computation is significantly more efficient in its use of resources than deterministic digital computation even at relatively high levels of precision in the cell. Based on this analysis, we conclude that synthetic biology must use analog, collective analog, probabilistic and hybrid analog-digital computational approaches; otherwise, even relatively simple synthetic computations in cells such as addition will exceed energy and molecular-count budgets. We present schematics for efficiently representing analog DNA-protein computation in cells. Analog electronic flow in subthreshold transistors and analog molecular flux in chemical reactions obey Boltzmann exponential laws of thermodynamics and are described by astoundingly similar logarithmic electrochemical potentials. Therefore, cytomorphic circuits can help to map circuit designs between electronic and biochemical domains. We review recent work that uses positive-feedback linearization circuits to architect wide-dynamic-range logarithmic analog computation in Escherichia coli using three transcription factors, nearly two orders of magnitude more efficient in parts than prior digital implementations. PMID:24567476

  17. Biological rhythms and preeclampsia

    Directory of Open Access Journals (Sweden)

    Agnès eDitisheim

    2013-04-01

    Full Text Available The impact of impaired circadian rhythm on health has been widely studied in shift workers and trans-meridian travelers. A part from its correlation with sleep and mood disorders, biological rhythm impairment is a recognized risk factor for cardiovascular diseases and breast cancer.Preeclampsia is a major public health issue, associated with a significant maternal and fetal morbidity and mortality worldwide. While the risks factors for this condition such as obesity, diabetes, pre-existing hypertension have been identified, the underlying mechanism of this multi-factorial disease is yet not fully understood.The disruption of the light/dark cycle in pregnancy has been associated with adverse outcomes. Slightly increased risk for small for gestational age babies, low birth weight babies and preterm deliveries has been reported in shift working women. Whether altered circadian cycle represents a risk factor for preeclampsia or preeclampsia is itself linked with an abnormal circadian cycle is less clear. There are only few reports available, showing conflicting results. In this review, we will discuss recent observations concerning circadian pattern of blood pressure in normotensive and hypertensive pregnancies. We explore the hypothesis that circadian misalignments may represent a risk factor for preeclampsia. Unraveling potential link between circadian clock gene and preeclampsia could offer a novel approach to our understanding of this multi-system disease specific to pregnancy.

  18. [Hemodialysis with biological object].

    Science.gov (United States)

    Eventov, V L; Maksimenko, V A; Zhidkov, I L; Andrianova, M Iu

    2005-01-01

    The essence of the method of biodialysis (hemodialysis with biological object) developed and suggested by the authors for clinical use consists in that the healthy organism exerts, through a system of mass transfer, a therapeutic action on the sick organism. Blood from the affected and healthy organisms is perfused through individual mass exchangers (dialyzers, hemodiafilters and hemofilters), which are hydraulically connected by a circulating transport medium. Metabolites that accumulate in blood of the affected organism diffuse into the transport medium and, from there, into blood of the healthy organism, which metabolizes them. The reverse process occurs simultaneously: substances, whose concentration in blood of the sick organism is less versus the healthy organism, diffuse from blood of the healthy organism to blood of patient. The method suggested by us can be used in clinical practice for normalizing a variety of parameters in patients with hepatic and renal insufficiency. Besides, a number of substances can be transferred from the healthy donor to patient in the process of biodialysis, which opens promising potentialities for the treatment of many diseases.

  19. Biological dosimetry; Dosimetria biologica

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Arceo M, C., E-mail: citlali.guerrero@inin.gob.m [ININ, Departamento de Biologia, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2010-07-01

    In the Instituto Nacional de Investigaciones Nucleares (ININ) the works to establish a laboratory of biological dosimetry were initiated in 1998, with the purpose that could assist any situation with respect to the exposition to radiation, so much of the occupational exposed personnel as of individuals not related with the handling of radio-active material. The first activity that was realized was to develop the corresponding curves in vitro of dose response for different qualities and radiation types. In the year 2000 the curve corresponding to the gamma radiation of {sup 60}Co was published and up to 2002 the curve corresponding to the X rays of 58 KeV, 120 and 250 kVp. In all the cases, the curves contain the requirements to be used in the determination of the exposition dose. At the present time the curves dose-response are developing for neutrons take place in the reactor Triga Mark III of ININ. Additionally to these activities, cases of suspicion of accidental exposition to radiation have been assisted, using in a beginning the curves published by the IAEA and, from the year 2000, the curves developed in the ININ. (Author)

  20. Eosinophils in glioblastoma biology

    Directory of Open Access Journals (Sweden)

    Curran Colleen S

    2012-01-01

    Full Text Available Abstract Glioblastoma multiforme (GBM is the most common primary brain tumor in adults. The development of this malignant glial lesion involves a multi-faceted process that results in a loss of genetic or epigenetic gene control, un-regulated cell growth, and immune tolerance. Of interest, atopic diseases are characterized by a lack of immune tolerance and are inversely associated with glioma risk. One cell type that is an established effector cell in the pathobiology of atopic disease is the eosinophil. In response to various stimuli, the eosinophil is able to produce cytotoxic granules, neuromediators, and pro-inflammatory cytokines as well as pro-fibrotic and angiogenic factors involved in pathogen clearance and tissue remodeling and repair. These various biological properties reveal that the eosinophil is a key immunoregulatory cell capable of influencing the activity of both innate and adaptive immune responses. Of central importance to this report is the observation that eosinophil migration to the brain occurs in response to traumatic brain injury and following certain immunotherapeutic treatments for GBM. Although eosinophils have been identified in various central nervous system pathologies, and are known to operate in wound/repair and tumorstatic models, the potential roles of eosinophils in GBM development and the tumor immunological response are only beginning to be recognized and are therefore the subject of the present review.