244 research outputs found
Fluctuation and fixation of rodenticide resistance alleles in Rattus norvegicus
Berthier, K., Benoit, E., Berny, P., Lasseur, R., Merville, A., Peigneaux, F., Cosson, J.-F
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P2Y12 Receptor Blockade Augments Glycoprotein IIbâIIIa Antagonist Inhibition of Platelet Activation, Aggregation, and Procoagulant Activity
Background: New antiplatelet agents that provide greater, more consistent inhibition of the platelet ADP receptor P2Y12 may be used in combination with glycoprotein (GP) IIbâIIIa antagonists, but their combined effect on platelet function and procoagulant activity is not well studied. Therefore, the objective of this study was to evaluate the independent and complementary effects of P2Y12 and GPIIbâIIIa inhibition on platelet function and procoagulant activity. Methods and Results: Healthy donor blood was treated with the active metabolite of prasugrel (Râ138727 5 ÎŒmol/L), GPIIbâIIIa antagonists (abciximab 3 ÎŒg/mL or eptifibatide 0.9 ÎŒg/mL), and combinations thereof, exposed to physiologically relevant agonists (collagen and ADP) and then evaluated for markers of platelet activation and procoagulant activity. Significant interactions between Râ138727 and GPIIbâIIIa antagonists were observed. Râ138727 and the GPIIbâIIIa antagonists had additive inhibitory effects on collagenâstimulated platelet aggregation and on the collagen plus ADPâstimulated level of activated platelet surface GPIIbâIIIa. Râ138727 and abciximab each inhibited collagen plus ADPâstimulated platelet phosphatidylserine expression and prothrombin cleavage, and the combination produced greater inhibition than achieved with abciximab alone. In contrast, eptifibatide did not inhibit, but instead enhanced, collagen plus ADPâstimulated prothrombin cleavage. Addition of Râ138727 reduced prothrombin cleavage in eptifibatideâtreated samples, suggesting a novel mechanism for potential benefit from combined prasugrel and eptifibatide treatment. Conclusions: The complementary effects of abciximab and Râ138727 on platelet activation, aggregation, and procoagulant activity suggest their combined use may, to a greater degree than with either agent alone, reduce thrombus formation in vivo
MATRIKS SCORE DAN APLIKASINYA DALAM PENGAMANAN PESAN RAHASIA
The exchange of general information or confidential information between two persons through a medium does not guarantee its safety. This makes the sender of information and the recipient of information needs to be vigilant. In this case, the role of data encoding is very important. One of the most commonly used and recognized data encryption is cryptography. Cryptography is a technique for encrypting data through the process of encryption and decryption process by using certain keys so as generate new data that is secret. One of the cryptography is the security of secret messages using the Score matrix. The score matrix is defined as a symmetric matrix with elements of complex number and is a diagonal matrix
Wildlife ecological risk assessment in the 21st century: Promising technologies to assess toxicological effects
Despite advances in toxicity testing and the development of new approach methodologies (NAMs) for hazard assessment, the ecological risk assessment (ERA) framework for terrestrial wildlife (i.e., airâbreathing amphibians, reptiles, birds, and mammals) has remained unchanged for decades. While survival, growth, and reproductive endpoints derived from whole-animal toxicity tests are central to hazard assessment, nonstandard measures of biological effects at multiple levels of biological organization (e.g., molecular, cellular, tissue, organ, organism, population, community, ecosystem) have the potential to enhance the relevance of prospective and retrospective wildlife ERAs. Other factors (e.g., indirect effects of contaminants on food supplies and infectious disease processes) are influenced by toxicants at individual, population, and community levels, and need to be factored into chemically based risk assessments to enhance the âecoâ component of ERAs. Regulatory and logistical challenges often relegate such nonstandard endpoints and indirect effects to post-registration evaluations of pesticides and industrial chemicals and contaminated site evaluations. While NAMs are being developed, to date, their applications in ERAs focused on wildlife have been limited. No single magic tool or model will address all uncertainties in hazard assessment. Modernizing wildlife ERAs will likely entail combinations of laboratoryâ and fieldâderived data at multiple levels of biological organization, knowledge collection solutions (e.g., systematic review, adverse outcome pathway frameworks), and inferential methods that facilitate integrations and risk estimations focused on species, populations, interspecific extrapolations, and ecosystem services modeling, with less dependence on wholeâanimal data and simple hazard ratios
A study protocol to investigate the relationship between dietary fibre intake and fermentation, colon cell turnover, global protein acetylation and early carcinogenesis: the FACT study
Background: A number of studies, notably EPIC, have shown a descrease in colorectal cancer risk associated with increased fibre consumption. Whilst the underlying mechanisms are likely to be multifactorial, production of the short-chain fatty-acid butyrate fro butyratye is frequently cited as a major potential contributor to the effect. Butyrate inhibits histone deacetylases, which work on a wide range of proteins over and above histones. We therefore hypothesized that alterations in the acetylated proteome may be associated with a cancer risk phenotype in the colorectal mucosa, and that such alterations are candidate biomarkers for effectiveness of fibre interventions in cancer prevention.
Methods an design: There are two principal arms to this study: (i) a cross-sectional study (FACT OBS) of 90 subjects recruited from gastroenterology clinics and; (ii) an intervention trial in 40 subjects with an 8 week high fibre intervention. In both studies the principal goal is to investigate a link between fibre intake, SCFA production and global protein acetylation. The primary measure is level of faecal butyrate, which it is hoped will be elevated by moving subjects to a high fibre diet. Fibre intakes will be estimated in the cross-sectional group using the EPIC Food Frequency Questionnaire. Subsidiary measures of the effect of butyrate on colon mucosal function and precancerous phenotype will include measures of apoptosis, apoptotic regulators cell cycle and cell division.
Discussion: This study will provide a new level of mechanistic data on alterations in the functional proteome in response to the colon microenvironment which may underwrite the observed cancer preventive effect of fibre. The study may yield novel candidate biomarkers of fibre fermentation and colon mucosal function
Pod indehiscence is a domestication and aridity resilience trait in common bean.
Plant domestication has strongly modified crop morphology and development. Nevertheless, many crops continue to display atavistic characteristics that were advantageous to their wild ancestors but are deleterious under cultivation, such as pod dehiscence (PD). Here, we provide the first comprehensive assessment of the inheritance of PD in the common bean (Phaseolus vulgaris), a major domesticated grain legume. Using three methods to evaluate the PD phenotype, we identified multiple, unlinked genetic regions controlling PD in a biparental population and two diversity panels. Subsequently, we assessed patterns of orthology among these loci and those controlling the trait in other species. Our results show that different genes were selected in each domestication and ecogeographic race. A chromosome Pv03 dirigent-like gene, involved in lignin biosynthesis, showed a base-pair substitution that is associated with decreased PD. This haplotype may underlie the expansion of Mesoamerican domesticates into northern Mexico, where arid conditions promote PD. The rise in frequency of the decreased-PD haplotype may be a consequence of the markedly different fitness landscape imposed by domestication. Environmental dependency and genetic redundancy can explain the maintenance of atavistic traits under domestication
A chromosome-scale assembly reveals chromosomal aberrations and exchanges generating genetic diversity in Coffea arabica germplasm
In order to better understand the mechanisms generating genetic diversity in the recent allotetraploid species Coffea arabica, here we present a chromosome-level assembly obtained with long read technology. Two genomic compartments with different structural and functional properties are identified in the two homoeologous genomes. The resequencing data from a large set of accessions reveals low intraspecific diversity in the center of origin of the species. Across a limited number of genomic regions, diversity increases in some cultivated genotypes to levels similar to those observed within one of the progenitor species, Coffea canephora, presumably as a consequence of introgressions deriving from the so-called Timor hybrid. It also reveals that, in addition to few, early-occurring exchanges between homoeologous chromosomes, there are numerous recent chromosomal aberrations including aneuploidies, deletions, duplications and exchanges. These events are still polymorphic in the germplasm and could represent a fundamental source of genetic variation in such a lowly variable species
Environmental NGOs at a crossroads?
Article published as introduction to the Special Issue 'Environmental Politics at a crossroads', edited by Nathalie Berny & Christopher Rootes, Environmental Politics vol.27.no.6, November 201
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