552 research outputs found

    A Simplified 8 × 8 Transformation And Quantization Real-Time Ip-Block For MPEG-4 H.264/AVC Applications: A New Design Flow Approach

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    Current multimedia design processes suffer from the excessively large time spent on testing new IP-blocks with references based on large video encoders specifications (usually several thousands lines of code). The appropriate testing of a single IP-block may require the conversion of the overall encoder from software to hardware, which is difficult to complete in the short time required by the competition-driven reduced time-to-market demanded for the adoption of a new video coding standard. This paper presents a new design flow to accelerate the conformance testing of an IP-block using the H.264/AVC software reference model. An example block of the simplified 8 × 8 transformation and quantization, which is adopted in FRExt, is provided as a case study demonstrating the effectiveness of the approach

    Identification and Functional Analysis of Temperate Siphoviridae Bacteriophages of Acinetobacter baumannii

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    Acinetobacter baumannii is an opportunistic pathogen that presents a serious clinical challenge due to its increasing resistance to all available antibiotics. Phage therapy has been introduced recently to treat antibiotic-incurable A. baumannii infections. In search for new A. baumannii specific bacteriophages, 20 clinical A. baumannii strains were used in two pools in an attempt to enrich phages from sewage. The enrichment resulted in induction of resident prophage(s) and three temperate bacteriophages, named vB_AbaS_fEg-Aba01, vB_AbaS_fLi-Aba02 and vB_AbaS_fLi-Aba03, all able to infect only one strain (#6597) of the 20 clinical strains, were isolated. Morphological characteristics obtained by transmission electron microscopy together with the genomic information revealed that the phages belong to the family Siphoviridae. The ca. 35 kb genomic sequences of the phages were >99% identical to each other. The linear ds DNA genomes of the phages contained 10 nt cohesive end termini, 52–54 predicted genes, an attP site and one tRNA gene each. A database search revealed an >99% identical prophage in the genome of A. baumannii strain AbPK1 (acc. no. CP024576.1). Over 99% identical prophages were also identified from two of the original 20 clinical strains (#5707 and #5920) and both were shown to be spontaneously inducible, thus very likely being the origins of the isolated phages. The phage vB_AbaS_fEg-Aba01 was also able to lysogenize the susceptible strain #6597 demonstrating that it was fully functional. The phages showed a very narrow host range infecting only two A. baumannii strains. In conclusion, we have isolated and characterized three novel temperate Siphoviridae phages that infect A. baumannii

    Carbetocin versus Oxytocin and Misoprostol in prevention of atonic post-partum hemorrhage in high risk patients planed for cesarean delivery

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    Background: Post-partum hemorrhage prevention (PPH) is considered a major issue due to its effect on maternal morbidity and mortality. The objective of this study was to compare efficacy of Carbetocin in prevention of atonic post-partum hemorrhage in high risk patients undergoing elective caesarean section in comparison to Oxytocin and Misoprostol.Methods: 150 pregnant women prepared for elective caesarean section were classified into 3 groups; Group I (50 patients received Carbetocin 100 mg I.V infusion), Group II (50 patients received 20 IU of Oxytocin infusion on 1000 ml of normal saline solution) and Group III (50 cases received Misoprostol 400 µg per rectum immediately before induction of anaesthesia). Assessment of PPH and its degree was determined according to amount of blood loss during and for first 24 hours of caesarean delivery, also further need for haemostatic measures were also assessed.Results: There was a statistically significant difference in PPH among the three groups 6, 14 and 12% for group I, II and III respectively (P <0.001), major PPH was 0, 4 and 6% for the same groups respectively (P <0.001). The need for additional uterotonic agents was significantly lesser in Group I compared to Group II and III (2% versus 8 and 12% respectively P = 0.02) also the need for additional surgical measures was significantly lesser among the three groups (P= 0.00). The drop in Hb level and haematocrit value was significantly lesser in group I compared to group II& III (P <0.05). The need for blood transfusion was significantly lesser in Group I compared to group II and III (0% versus 12% p <0.0001)Conclusions: Carbetocin was superior to Oxytocin and Misoprostol in prevention of atonic PPH in high risk patients underwent elective caesarean delivery. Carbetocin should be administered for all cases undergoing elective CS and carry a risk factor for postpartum hemorrhage.

    A genomewide association study in divergently selected lines in rabbits reveals novel genomic regions associated with litter size traits

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    [EN] Uterine capacity (UC), defined as the total number of kits from unilaterally ovariectomized does at birth, has a high genetic correlation with litter size. The aim of our research was to identify genomic regions associated with litter size traits through a genome-wide association study using rabbits from a divergent selection experiment for UC. A high-density SNP array (200K) was used to genotype 181 does from a control population, high and low UC lines. Traits included total number born (TNB), number born alive (NBA), number born dead, ovulation rate (OR), implanted embryos (IE), and embryo, foetal and prenatal survivals at second parity. We implemented the Bayes B method and the associations were tested by Bayes factors and the percentage of genomic variance (GV) explained by windows. Different genomic regions associated with TNB, NBA, IE, and OR were found. These regions explained 7.36%, 1.27%, 15.87%, and 3.95% of GV, respectively. Two consecutive windows on chromosome 17 were associated with TNB, NBA, and IE. This genomic region accounted for 6.32% of GV of TNB. In this region, we found the BMP4, PTDGR, PTGER2, STYX and CDKN3 candidate genes which presented functional annotations linked to some reproductive processes. Our findings suggest that a genomic region on chromosome 17 has an important effect on litter size traits. However, further analyses are needed to validate this region in other maternal rabbit lines.The work was funded by project AGL2014-55921-C2-1-P from the National Programme for Fostering Excellence in Scientific and Technical Research Project I+D. B. Samuel Sosa-Madrid was supported by a grant from the National Secretariat of Science, Technology, and Innovation of Panama (SENACYT) for a master's degree (the first stage of this study): BECA-2199-40-2012. Also, he was supported by an FPI grant from the Ministry of Economy and Competitiveness of Spain (the second stage of this study): BES-2015-074194.Sosa-Madrid, BS.; Santacreu Jerez, MA.; Blasco Mateu, A.; Fontanesi, L.; Pena, R.; Ibáñez-Escriche, N. (2020). A genomewide association study in divergently selected lines in rabbits reveals novel genomic regions associated with litter size traits. Journal of Animal Breeding and Genetics. 137(2):123-138. https://doi.org/10.1111/jbg.12451S1231381372Aken, B. L., Ayling, S., Barrell, D., Clarke, L., Curwen, V., Fairley, S., … Searle, S. M. J. (2016). The Ensembl gene annotation system. Database, 2016, baw093. doi:10.1093/database/baw093Al-Samerria, S., Al-Ali, I., McFarlane, J. R., & Almahbobi, G. (2015). The impact of passive immunisation against BMPRIB and BMP4 on follicle development and ovulation in mice. REPRODUCTION, 149(5), 403-411. doi:10.1530/rep-14-0451Argente, M. J., Merchán, M., Peiró, R., García, M. L., Santacreu, M. A., Folch, J. M., & Blasco, A. (2010). Candidate gene analysis for reproductive traits in two lines of rabbits divergently selected for uterine capacity1. Journal of Animal Science, 88(3), 828-836. doi:10.2527/jas.2009-2324Argente, M. J., Santacreu, M. A., Climent, A., Bolet, G., & Blasco, A. (1997). Divergent selection for uterine capacity in rabbits. Journal of Animal Science, 75(9), 2350. doi:10.2527/1997.7592350xAshburner, M., Ball, C. A., Blake, J. A., Botstein, D., Butler, H., Cherry, J. M., … Sherlock, G. (2000). Gene Ontology: tool for the unification of biology. Nature Genetics, 25(1), 25-29. doi:10.1038/75556Ballester, M., Castelló, A., Peiró, R., Argente, M. J., Santacreu, M. A., & Folch, J. M. (2012). Identification of differentially expressed genes in the oviduct of two rabbit lines divergently selected for uterine capacity using suppression subtractive hybridization. Animal Genetics, 44(3), 296-304. doi:10.1111/age.12005Bergfelder-Drüing, S., Grosse-Brinkhaus, C., Lind, B., Erbe, M., Schellander, K., Simianer, H., & Tholen, E. (2015). A Genome-Wide Association Study in Large White and Landrace Pig Populations for Number Piglets Born Alive. PLOS ONE, 10(3), e0117468. doi:10.1371/journal.pone.0117468Blasco, A., Argente, M. J., Haley, C. S., & Santacreu, M. A. (1994). Relationships between components of litter size in unilaterally ovariectomized and intact rabbit does. Journal of Animal Science, 72(12), 3066-3072. doi:10.2527/1994.72123066xBlasco, A., Ortega, J. A., Climent, A., & Santacreu, M. A. (2005). Divergent selection for uterine capacity in rabbits. I. Genetic parameters and response to selection1. Journal of Animal Science, 83(10), 2297-2302. doi:10.2527/2005.83102297xBlasco, A., & Pena, R. N. (2018). Current Status of Genomic Maps: Genomic Selection/GBV in Livestock. Animal Biotechnology 2, 61-80. doi:10.1007/978-3-319-92348-2_4Browning, B. L., & Browning, S. R. (2009). A Unified Approach to Genotype Imputation and Haplotype-Phase Inference for Large Data Sets of Trios and Unrelated Individuals. The American Journal of Human Genetics, 84(2), 210-223. doi:10.1016/j.ajhg.2009.01.005Carneiro, M., Afonso, S., Geraldes, A., Garreau, H., Bolet, G., Boucher, S., … Ferrand, N. (2011). The Genetic Structure of Domestic Rabbits. Molecular Biology and Evolution, 28(6), 1801-1816. doi:10.1093/molbev/msr003Carneiro, M., Rubin, C.-J., Di Palma, F., Albert, F. W., Alfoldi, J., Barrio, A. M., … Andersson, L. (2014). Rabbit genome analysis reveals a polygenic basis for phenotypic change during domestication. Science, 345(6200), 1074-1079. doi:10.1126/science.1253714Cartuche, L., Pascual, M., Gómez, E. A., & Blasco, A. (2014). Economic weights in rabbit meat production. World Rabbit Science, 22(3), 165. doi:10.4995/wrs.2014.1747Cesar, A. S., Regitano, L. C., Mourão, G. B., Tullio, R. R., Lanna, D. P., Nassu, R. T., … Coutinho, L. L. (2014). Genome-wide association study for intramuscular fat deposition and composition in Nellore cattle. BMC Genetics, 15(1), 39. doi:10.1186/1471-2156-15-39Christenson, R. K., Leymaster, K. A., & Young, L. D. (1987). Justification of Unilateral Hysterectomy-Ovariectomy as a Model to Evaluate Uterine Capacity in Swine. Journal of Animal Science, 65(3), 738-744. doi:10.2527/jas1987.653738xDing, X., Zhang, X., Mu, Y., Li, Y., & Hao, J. (2012). Effects of BMP4/SMAD signaling pathway on mouse primordial follicle growth and survival via up-regulation ofSohlh2andc-kit. Molecular Reproduction and Development, 80(1), 70-78. doi:10.1002/mrd.22138Fan, B., Du, Z.-Q., Gorbach, D. M., & Rothschild, M. F. (2010). Development and Application of High-density SNP Arrays in Genomic Studies of Domestic Animals. Asian-Australasian Journal of Animal Sciences, 23(7), 833-847. doi:10.5713/ajas.2010.r.03Garrick, D. J., & Fernando, R. L. (2013). Implementing a QTL Detection Study (GWAS) Using Genomic Prediction Methodology. Genome-Wide Association Studies and Genomic Prediction, 275-298. doi:10.1007/978-1-62703-447-0_11Goggolidou, P., Soneji, S., Powles-Glover, N., Williams, D., Sethi, S., Baban, D., … Norris, D. P. (2013). A chronological expression profile of gene activity during embryonic mouse brain development. Mammalian Genome, 24(11-12), 459-472. doi:10.1007/s00335-013-9486-7Jiao, X., Sherman, B. T., Huang, D. W., Stephens, R., Baseler, M. W., Lane, H. C., & Lempicki, R. A. (2012). DAVID-WS: a stateful web service to facilitate gene/protein list analysis. Bioinformatics, 28(13), 1805-1806. doi:10.1093/bioinformatics/bts251Kass, R. E., & Raftery, A. E. (1995). Bayes Factors. Journal of the American Statistical Association, 90(430), 773-795. doi:10.1080/01621459.1995.10476572Kessner, D., & Novembre, J. (2015). Power Analysis of Artificial Selection Experiments Using Efficient Whole Genome Simulation of Quantitative Traits. Genetics, 199(4), 991-1005. doi:10.1534/genetics.115.175075Konno, T., Pinho Melo, E., Lopes, C., Mehmeti, I., Lenzen, S., Ron, D., & Avezov, E. (2015). ERO1-independent production of H2O2 within the endoplasmic reticulum fuels Prdx4-mediated oxidative protein folding. Journal of Cell Biology, 211(2), 253-259. doi:10.1083/jcb.201506123Laborda, P., Mocé, M. L., Blasco, A., & Santacreu, M. A. (2012). Selection for ovulation rate in rabbits: Genetic parameters and correlated responses on survival rates1. Journal of Animal Science, 90(2), 439-446. doi:10.2527/jas.2011-4219Laborda, P., Mocé, M. L., Santacreu, M. A., & Blasco, A. (2011). Selection for ovulation rate in rabbits: Genetic parameters, direct response, and correlated response on litter size1. Journal of Animal Science, 89(10), 2981-2987. doi:10.2527/jas.2011-3906Lehermeier, C., Wimmer, V., Albrecht, T., Auinger, H.-J., Gianola, D., Schmid, V. J., & Schön, C.-C. (2013). Sensitivity to prior specification in Bayesian genome-based prediction models. Statistical Applications in Genetics and Molecular Biology, 12(3). doi:10.1515/sagmb-2012-0042Li, Y., & Parast, M. M. (2014). BMP4 regulation of human trophoblast development. The International Journal of Developmental Biology, 58(2-3-4), 239-246. doi:10.1387/ijdb.130341mpLópez de Maturana, E., Ibáñez-Escriche, N., González-Recio, Ó., Marenne, G., Mehrban, H., Chanock, S. J., … Malats, N. (2014). Next generation modeling in GWAS: comparing different genetic architectures. Human Genetics, 133(10), 1235-1253. doi:10.1007/s00439-014-1461-1Marras, G., Rossoni, A., Schwarzenbacher, H., Biffani, S., Biscarini, F., & Nicolazzi, E. L. (2016). zanardi: an open-source pipeline for multiple-species genomic analysis of SNP array data. Animal Genetics, 48(1), 121-121. doi:10.1111/age.12485Matzuk, M. M., & Lamb, D. J. (2002). Genetic dissection of mammalian fertility pathways. Nature Cell Biology, 4, S33-S40. doi:10.1038/ncb-nm-fertilitys41Merchán, M., Peiró, R., Argente, M. J., Santacreu, M. A., García, M. L., Blasco, A., & Folch, J. M. (2009). Analysis of theoviductal glycoprotein 1polymorphisms and their effects on components of litter size in rabbits. Animal Genetics, 40(5), 756-758. doi:10.1111/j.1365-2052.2009.01898.xMocé, M. L., Santacreu, M. A., Climent, A., & Blasco, A. (2004). The effect of divergent selection for uterine capacity on fetal and placental development at term in rabbits: Maternal and embryonic genetic effects1. Journal of Animal Science, 82(4), 1046-1052. doi:10.1093/ansci/82.4.1046Mocé, M. L., Santacreu, M. A., Climent, A., & Blasco, A. (2005). Divergent selection for uterine capacity in rabbits. III. Responses in uterine capacity and its components estimated with a cryopreserved control population1. Journal of Animal Science, 83(10), 2308-2312. doi:10.2527/2005.83102308xOnteru, S. K., Fan, B., Du, Z.-Q., Garrick, D. J., Stalder, K. J., & Rothschild, M. F. (2011). A whole-genome association study for pig reproductive traits. Animal Genetics, 43(1), 18-26. doi:10.1111/j.1365-2052.2011.02213.xOnteru, S. K., Gorbach, D. M., Young, J. M., Garrick, D. J., Dekkers, J. C. M., & Rothschild, M. F. (2013). Whole Genome Association Studies of Residual Feed Intake and Related Traits in the Pig. PLoS ONE, 8(6), e61756. doi:10.1371/journal.pone.0061756Peiró, R., Merchán, M., Santacreu, M. A., Argente, M. J., García, M. L., Folch, J. M., & Blasco, A. (2008). Identification of Single-Nucleotide Polymorphism in the Progesterone Receptor Gene and Its Association With Reproductive Traits in Rabbits. Genetics, 180(3), 1699-1705. doi:10.1534/genetics.108.090779Piles, M., García, M. L., Rafel, O., Ramon, J., & Baselga, M. (2006). Genetics of litter size in three maternal lines of rabbits: Repeatability versus multiple-trait models. Journal of Animal Science, 84(9), 2309-2315. doi:10.2527/jas.2005-622Quinton, V. M., Wilton, J. W., Robinson, J. A., & Mathur, P. K. (2006). Economic weights for sow productivity traits in nucleus pig populations. Livestock Science, 99(1), 69-77. doi:10.1016/j.livprodsci.2005.06.002Ragab, M., Sánchez, J. P., Mínguez, C., Vicente, J. S., & Baselga, M. (2014). Litter size components in a full diallel cross of four maternal lines of rabbits1. Journal of Animal Science, 92(8), 3231-3236. doi:10.2527/jas.2013-7286Rosenbloom, K. R., Armstrong, J., Barber, G. P., Casper, J., Clawson, H., Diekhans, M., … Kent, W. J. (2014). The UCSC Genome Browser database: 2015 update. Nucleic Acids Research, 43(D1), D670-D681. doi:10.1093/nar/gku1177Ros-Freixedes, R., Gol, S., Pena, R. N., Tor, M., Ibáñez-Escriche, N., Dekkers, J. C. M., & Estany, J. (2016). Genome-Wide Association Study Singles Out SCD and LEPR as the Two Main Loci Influencing Intramuscular Fat Content and Fatty Acid Composition in Duroc Pigs. PLOS ONE, 11(3), e0152496. doi:10.1371/journal.pone.0152496Rossitto, M., Ujjan, S., Poulat, F., & Boizet-Bonhoure, B. (2015). Multiple roles of the prostaglandin D2 signaling pathway in reproduction. REPRODUCTION, 149(1), R49-R58. doi:10.1530/rep-14-0381Santacreu, M. A., Mocé, M. L., Climent, A., & Blasco, A. (2005). Divergent selection for uterine capacity in rabbits. II. Correlated response in litter size and its components estimated with a cryopreserved control population1. Journal of Animal Science, 83(10), 2303-2307. doi:10.2527/2005.83102303xSchneider, J. F., Nonneman, D. J., Wiedmann, R. T., Vallet, J. L., & Rohrer, G. A. (2014). Genomewide association and identification of candidate genes for ovulation rate in swine12. Journal of Animal Science, 92(9), 3792-3803. doi:10.2527/jas.2014-7788Schneider, J. F., Rempel, L. A., Snelling, W. M., Wiedmann, R. T., Nonneman, D. J., & Rohrer, G. A. (2012). Genome-wide association study of swine farrowing traits. Part II: Bayesian analysis of marker data1,2. Journal of Animal Science, 90(10), 3360-3367. doi:10.2527/jas.2011-4759Stelzer, G., Rosen, N., Plaschkes, I., Zimmerman, S., Twik, M., Fishilevich, S., … Lancet, D. (2016). The GeneCards Suite: From Gene Data Mining to Disease Genome Sequence Analyses. Current Protocols in Bioinformatics, 54(1). doi:10.1002/cpbi.5Stephens, M., & Balding, D. J. (2009). Bayesian statistical methods for genetic association studies. Nature Reviews Genetics, 10(10), 681-690. doi:10.1038/nrg2615Toosi, A., Fernando, R. L., & Dekkers, J. C. M. (2018). Genome-wide mapping of quantitative trait loci in admixed populations using mixed linear model and Bayesian multiple regression analysis. Genetics Selection Evolution, 50(1). doi:10.1186/s12711-018-0402-1H.M., Y., Kumar, S., Dubey, P. P., Modi, R. P., Chaudhary, R., A., S. K., … B., S. (2017). Profiling of sperm gene transcripts in crossbred ( Bos taurus x Bos indicus ) bulls. Animal Reproduction Science, 177, 25-34. doi:10.1016/j.anireprosci.2016.12.003Zeisel, S. H. (2011). The supply of choline is important for fetal progenitor cells. Seminars in Cell & Developmental Biology, 22(6), 624-628. doi:10.1016/j.semcdb.2011.06.002Ziadi, C., Mocé, M. L., Laborda, P., Blasco, A., & Santacreu, M. A. (2013). Genetic selection for ovulation rate and litter size in rabbits: Estimation of genetic parameters and direct and correlated responses1. Journal of Animal Science, 91(7), 3113-3120. doi:10.2527/jas.2012-604

    Preparation of Ecofriendly Formulations Containing Biologically Active Monoterpenes with Their Fumigant and Residual Toxicities against Adults of Culex pipiens

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    Different mixtures of monoterpenes (ketone, alcohol, and alkene) were loaded on paper discs and wax and their knockdown activities were evaluated against Culex pipiens adults. Some individual monoterpenes were also evaluated by residual toxicity technique. Citronella oil as a reference was also loaded separately or in combination with monoterpenes on paper discs and wax. The ketone monoterpenes mixture (camphor, menthone, carvone, and fenchone) on paper discs was the most active (KT50 = 17.20 min) followed by ketone monoterpenes with citronella oil (KT50 = 20.79 min) and citronella oil alone (KT50 = 28.72 min). Wax formulations proved that the ketone and alcohol (geraniol, thymol, and menthol) monoterpenes gave the most activity as knockdown (KT50 = 31.79 and 43.39 min, resp.). Alcohol monoterpenes formulation recorded KT50 = 43.39 min. Residual activity of tested individual monoterpenes reported that the menthol was more toxic than camphor and camphene. Generally, this study suggests that the monoterpenes have the properties, which make them used as eco-friendly compounds in the control programs of Cx. pipiens adult. The use of paper discs is more applicable than wax in the adulticidal formulations

    Cross-sectional evaluation of the Bronchitis Severity Score in Egyptian children: A move to reduce antibiotics

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    Background. Despite evidence of limited benefit of antibiotics in acute bronchitis, most paediatric patients are prescribed them.Objectives. To assess the validity of the Bronchitis Severity Score (BSS) in assessing the clinical response to treatment of acute bronchitis, and determine whether clinical data and basic laboratory measurements can be used to guide antibiotic prescription.Methods. We enrolled 200 patients (age range 6 months - 12 years) with clinically diagnosed acute bronchitis. They were divided into three groups according to age. All patients were evaluated three times during the bronchitis episode (days 0, 5 and 7). The primary outcome measurement was the change in the BSS from day 0 to day 7.Results. On the initial visit, the mean (standard deviation (SD)) BSS was 8.36 (2.6), indicating moderate severity of bronchitis. The mean BSS decreased to 4.03 (2.3) on day 5 and to 2.36 (1.45) on day 7. Initial blood tests showed anaemia (80%), leucocytosis (6%), bandaemia (3%) and lymphocytosis (52%). Only four patients were positive for C-reactive protein, while the erythrocyte sedimentation rate was elevated in 98% of cases. There were significant correlations between bandaemia, fever grade (p&lt;0.001) and white blood cell count with clinical variables such as the presence of secretions on chest auscultation (p&lt;0.05) and toxic facies on general examination (p&lt;0.05).Conclusions. Acute bronchitis in children is a self-limiting disease that does not require routine administration of antibiotics. The BSS is a simple and practical clinical scoring system that is useful in evaluating disease severity and monitoring disease resolution in acute bronchitis

    An environmentally benign antimicrobial nanoparticle based on a silver-infused lignin core

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    Silver nanoparticles have antibacterial properties, but their use has been a cause for concern because they persist in the environment. Here, we show that lignin nanoparticles infused with silver ions and coated with a cationic polyelectrolyte layer form a biodegradable and green alternative to silver nanoparticles. The polyelectrolyte layer promotes the adhesion of the particles to bacterial cell membranes and, together with silver ions, can kill a broad spectrum of bacteria, including Escherichia coli, Pseudomonas aeruginosa and quaternary-amine-resistant Ralstonia sp. Ion depletion studies have shown that the bioactivity of these nanoparticles is time-limited because of the desorption of silver ions. High-throughput bioactivity screening did not reveal increased toxicity of the particles when compared to an equivalent mass of metallic silver nanoparticles or silver nitrate solution. Our results demonstrate that the application of green chemistry principles may allow the synthesis of nanoparticles with biodegradable cores that have higher antimicrobial activity and smaller environmental impact than metallic silver nanoparticles

    The steroid and xenobiotic receptor (SXR), beyond xenobiotic metabolism

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    The steroid and xenobiotic receptor (SXR) (also known as pregnane X receptor or PXR) is a nuclear hormone receptor activated by a diverse array of endogenous hormones, dietary steroids, pharmaceutical agents, and xenobiotic compounds. SXR has an enlarged, flexible, hydrophobic ligand binding domain (LBD) which is remarkably divergent across mammalian species and SXR exhibits considerable differences in its pharmacology among mammals. The broad response profile of SXR has led to the development of "the steroid and xenobiotic sensor hypothesis". SXR has been established as a xenobiotic sensor that coordinately regulates xenobiotic clearance in the liver and intestine via induction of genes involved in drug and xenobiotic metabolism. In the past few years, research has revealed new and mostly unsuspected roles for SXR in modulating inflammation, bone homeostasis, vitamin D metabolism, lipid homeostasis, energy homeostasis and cancer. The identification of SXR as a xenobiotic sensor has provided an important tool for studying new mechanisms through which diet, chemical exposure, and environment ultimately impact health and disease. The discovery and pharmacological development of new PXR modulators might represent an interesting and innovative therapeutic approach to combat various diseases
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