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951.
Mouchtouri V Velonakis E Tsakalof A Kapoula C Goutziana G Vatopoulos A Kremastinou J Hadjichristodoulou C 《Applied and environmental microbiology》2007,73(5):1489-1492
The Legionella colonization frequency at 385 Greek hotel hot and cold water distribution systems was 20.8%. Legionella contamination was associated with the presence of an oil heater (odds ratio [OR]=2.04, 95% confidence interval [CI]=1.12 to 3.70), with the sample temperature (OR=0.26, 95% CI=0.1 to 0.5), with seasonal operation (OR=3.23, 95% CI=1.52 to 6.87), and with the presence of an independent disinfection system (OR=0.30, 95% CI=0.15 to 0.62). The same water temperatures, free-chlorine levels, and pHs differently affect the survival of various Legionella spp. 相似文献
952.
Laurence Flori Katayoun Moazami‐Goudarzi Vronique Alary Abdelillah Araba Ismaïl Boujenane Nadjet Boushaba Franois Casabianca Sara Casu Roberta Ciampolini Armelle Coeur D'Acier Corinne Coquelle Juan‐Vicente Delgado Ahmed El‐Beltagi Georgia Hadjipavlou Emmanuelle Jousselin Vincenzo Landi Anne Lauvie Philippe Lecomte Christina Ligda Caroline Marinthe Amparo Martinez Salvatore Mastrangelo Dalal Menni Charles‐Henri Moulin Mona‐Abdelzaher Osman Olivier Pineau Baldassare Portolano Clementina Rodellar Nadhira Saïdi‐Mehtar Tiziana Sechi Guilhem Sempr Sophie Thvenon Dimitrios Tsiokos Denis Laloë Mathieu Gautier 《Molecular ecology》2019,28(5):1009-1029
Domestic species such as cattle (Bos taurus taurus and B. t. indicus) represent attractive biological models to characterize the genetic basis of short‐term evolutionary response to climate pressure induced by their post‐domestication history. Here, using newly generated dense SNP genotyping data, we assessed the structuring of genetic diversity of 21 autochtonous cattle breeds from the whole Mediterranean basin and performed genome‐wide association analyses with covariables discriminating the different Mediterranean climate subtypes. This provided insights into both the demographic and adaptive histories of Mediterranean cattle. In particular, a detailed functional annotation of genes surrounding variants associated with climate variations highlighted several biological functions involved in Mediterranean climate adaptation such as thermotolerance, UV protection, pathogen resistance or metabolism with strong candidate genes identified (e.g., NDUFB3, FBN1, METTL3, LEF1, ANTXR2 and TCF7). Accordingly, our results suggest that main selective pressures affecting cattle in Mediterranean area may have been related to variation in heat and UV exposure, in food resources availability and in exposure to pathogens, such as anthrax bacteria (Bacillus anthracis). Furthermore, the observed contribution of the three main bovine ancestries (indicine, European and African taurine) in these different populations suggested that adaptation to local climate conditions may have either relied on standing genomic variation of taurine origin, or adaptive introgression from indicine origin, depending on the local breed origins. Taken together, our results highlight the genetic uniqueness of local Mediterranean cattle breeds and strongly support conservation of these populations. 相似文献
953.
P.A.F. Pacheco R.M.S. Galvão A.F.M. Faria N.l. Von Ranke M.S. Rangel T.M. Ribeiro M.l. Bello C.R. Rodrigues V.F. Ferreira D.R. da Rocha R.X. Faria 《Bioorganic & medicinal chemistry》2019,27(8):1449-1455
Extracellular adenosine 5′-triphosphate (ATP) triggers the P2X7 receptor (P2X7R) ionic channel to stimulate the release of the interleukin-IL-1β cytokine into macrophages. The current study explored the reaction of six structurally diverse triazole derivatives on P2X7-mediated dye uptake into murine peritoneal macrophages. P2X7R activity determined by ATP-evoked fluorescent dye uptake. Triazole derivatives toxicity measured using dextran rhodamine exclusion based colorimetric assay. A740004 and BBG, both P2X7R antagonist, inhibited ATP-induced dye uptake. In contrast, the derivatives 5a, 5b, 5e, and 5f did not diminish P2X7R activity in concentrations until 100?µM. 5c and 5d analogs caused a potent inhibitory activity on P2X7-induced dye uptake. Dextran Rhodamine exclusion measurements after 24?h of continuous treatment with triazole derivatives indicated a moderated toxicity for all molecules. In conclusion, this study showed that a series of new hybrid 1,2,3-triazolic naphthoquinones reduces P2X7R-induced dye uptake into murine macrophages. In silico analysis indicates a good pharmacokinetic profile and molecular docking results of these analogs indicate the potential to bind into an allosteric site located into the P2X7R pore and juxtaposed with the ATP binding pocket. In this manner, the compounds 5c and 5d may be used as a scaffold for new P2X7R inhibitors with reduced toxicity, and good anti-inflammatory activity. 相似文献
954.
Nemesio Villa‐Ruano Yesenia Pacheco‐Hernndez Jos Alejo Zrate‐Reyes Ramiro Cruz‐Durn Edmundo Lozoya‐Gloria 《化学与生物多样性》2019,16(2)
Zanthoxylum limoncello is a native plant from southern Mexico which is used as a timber source, condiment and as a traditional medicine. Herein, we report on the volatile content of the leaf essential oil and its biological activities. The annual essential oils (2015–2018) contained volatile organic compounds which exhibited a moderate growth inhibitory activity against H. pylori ATCC 53504 (MIC 121.4–139.7 μg mL?1), 26695 (MIC 85.5–94.9 μg mL?1) and J99 (MIC 94.7–110.4 μg mL?1). These hydrodistillates contained 2‐undecanone (31.6–36.8 %; MIC 185.3–199.2 μg mL?1) and 2‐undecenal (25.1–35.7 %; MIC 144.8–111.3 μg mL?1) as the most abundant compounds which were partially involved in the anti‐H. pylori activity. The human ornithine decarboxylase enzyme (ODC1), which shows increased activity in several cancer types, was non‐competitively inhibited (Vmax 2.7>0.8 Kcat s?1) by the essential oil of Z. limoncello as well as by 2‐undecanone and 2‐undecenal in accordance to in vitro kinetic studies. In silico calculations strongly suggest that the carbonyl group of these oxygenated hydrocarbons interacts with both Asn319 and Ala39 at the subunit A of ODC1. Considering that Ala39 is located close to Asn44, a crucial amino acid of the ODC's allosteric site, the non‐competitive inhibition of the enzyme by 2‐undecanone and 2‐undecenal is endorsed. Finally, the essential oil of Z. limoncello and its main volatiles showed a significant (p<0.01) and prolonged repellent effect against Aedes aegypti. 相似文献
955.
Xiaoying Shen Ryan Duffy Robert Howington Alethea Cope Shanmugalakshmi Sadagopal Haesun Park Ranajit Pal Suefen Kwa Song Ding Otto O. Yang Genevieve G. Fouda Roger Le Grand Diane Bolton Mariano Esteban Sanjay Phogat Mario Roederer Rama R. Amara Louis J. Picker Robert A. Seder M. Juliana McElrath Susan Barnett Sallie R. Permar Robin Shattock Anthony L. DeVico Barbara K. Felber George N. Pavlakis Giuseppe Pantaleo Bette T. Korber David C. Montefiori Georgia D. Tomaras 《Journal of virology》2015,89(16):8643-8650
To evaluate antibody specificities induced by simian immunodeficiency virus (SIV) versus human immunodeficiency virus type 1 (HIV-1) envelope antigens in nonhuman primate (NHP), we profiled binding antibody responses to linear epitopes in NHP studies with HIV-1 or SIV immunogens. We found that, overall, HIV-1 Env IgG responses were dominated by V3, with the notable exception of the responses to the vaccine strain A244 Env that were dominated by V2, whereas the anti-SIVmac239 Env responses were dominated by V2 regardless of the vaccine regimen. 相似文献
956.
957.
Nikolaos I. Papadimitriou Michael E. Kainourgiakis Stylianos N. Karozis Georgia Ch. Charalambopoulou 《Molecular simulation》2015,41(13):1122-1136
Molecular dynamics simulations are performed on a lipid bilayer that consists of ceramide NS 24:0 in an attempt to examine several structural and physicochemical properties of the specific system. The simulations are carried out with five different force fields (OPLS, GROMOS, BERGER, CHARMM and GAFF) in order to evaluate and compare their performance in modelling lipid systems that contain ceramides. The examined properties include bilayer thickness, chain tilt, density profiles, order parameters, chain conformation, area per lipid and (intermolecular or intramolecular) hydrogen bonding between the head groups. Special focus is given to the lateral lipid arrangement. To this purpose, a method is proposed that utilises the radial distribution functions of the alkyl chains to derive quantitative information about the lateral lipid packing. In most cases, all force fields lead to similar results. For a few properties (e.g. intramolecular hydrogen bonding), there is some discrepancy between the force fields but the lack of respective experimental data does not allow an unambiguous conclusion on which force field is the most reliable. 相似文献
958.
Pedro Mendes-Moreira Mara L. Alves Zlatko Satovic Jo?o Pacheco dos Santos Jo?o Nina Santos Jo?o Candido Souza Silas E. Pêgo Arnel R. Hallauer Maria Carlota Vaz Patto 《PloS one》2015,10(4)
Maize ear fasciation
Knowledge of the genes affecting maize ear inflorescence may lead to better grain yield modeling. Maize ear fasciation, defined as abnormal flattened ears with high kernel row number, is a quantitative trait widely present in Portuguese maize landraces.Material and Methods
Using a segregating population derived from an ear fasciation contrasting cross (consisting of 149 F2:3 families) we established a two location field trial using a complete randomized block design. Correlations and heritabilities for several ear fasciation-related traits and yield were determined. Quantitative Trait Loci (QTL) involved in the inheritance of those traits were identified and candidate genes for these QTL proposed.Results and Discussion
Ear fasciation broad-sense heritability was 0.73. Highly significant correlations were found between ear fasciation and some ear and cob diameters and row number traits. For the 23 yield and ear fasciation-related traits, 65 QTL were identified, out of which 11 were detected in both environments, while for the three principal components, five to six QTL were detected per environment. Detected QTL were distributed across 17 genomic regions and explained individually, 8.7% to 22.4% of the individual traits or principal components phenotypic variance. Several candidate genes for these QTL regions were proposed, such as bearded-ear1, branched silkless1, compact plant1, ramosa2, ramosa3, tasselseed4 and terminal ear1. However, many QTL mapped to regions without known candidate genes, indicating potential chromosomal regions not yet targeted for maize ear traits selection.Conclusions
Portuguese maize germplasm represents a valuable source of genes or allelic variants for yield improvement and elucidation of the genetic basis of ear fasciation traits. Future studies should focus on fine mapping of the identified genomic regions with the aim of map-based cloning. 相似文献959.
Lucia Elena Alvarado-Arnez Evaldo P. Amaral Carolinne Sales-Marques Sandra M. B. Dur?es Cynthia C. Cardoso Euzenir Nunes Sarno Antonio G. Pacheco Francisco C. F. Lana Milton Ozório Moraes 《PloS one》2015,10(9)
Leprosy is a chronic infectious disease that depends on the interplay of several factors. Single nucleotide polymorphisms (SNPs) in host immune related genes have been consistently suggested as participants in susceptibility towards disease. Interleukin-10 (IL-10) is a crucial immunomodulatory cytokine in mycobacterial pathogenesis and especially the -819C>T SNP (rs1800871) has been tested in several case-control studies indicating association with leprosy risk, although a recent consensus estimate is still missing. In this study, we evaluated the association of the -819C>T SNP and leprosy in two new Brazilian family-based populations. Then, we performed meta-analysis for this polymorphism summarizing published studies including these Brazilian family-based groups. Finally, we also retrieved published studies for other distal and proximal IL10 polymorphisms: -3575 T>A (rs1800890), -2849 G>A (rs6703630), -2763 C>A (rs6693899), -1082 G>A (rs1800896) and -592 C>A (rs1800872). Results from meta-analysis supported a significant susceptibility association for the -819T allele, with pooled Odds Ratio of 1.22 (CI = 1.11–1.34) and P-value = 3x10–5 confirming previous data. This result remained unaltered after inclusion of the Brazilian family-based groups (OR = 1.2, CI = 1.10–1.31, P-value = 2x10–5). Also, meta-analysis confirmed association of -592 A allele and leprosy outcome (OR = 1.24, CI = 1.03–1.50, P-value = 0.02). In support of this, linkage disequilibrium analysis in 1000 genomes AFR, EUR, ASN and AMR populations pointed to r2 = 1.0 between the -592C>A and -819C>T SNPs. We found no evidence of association for the other IL10 polymorphisms analyzed for leprosy outcome. Our results reinforce the role of the -819C>T as a tag SNP (rs1800871) and its association with leprosy susceptibility. 相似文献
960.
Carlos José de Paula Silva Ana Clara Mour?o Moura Paula Cristina Pelli Paiva Raquel Concei??o Ferreira Rafaella Almeida Silvestrini Andréa Maria Duarte Vargas Liliam Pacheco Pinto de Paula Marcelo Drummond Naves Efigênia Ferreira e Ferreira 《PloS one》2015,10(8)
The aim of the present study was to analyze the spatial pattern of cases of maxillofacial injuries caused by interpersonal violence, based on the location of the victim’s residence, and to investigate the existence of conditions of socio-spatial vulnerability in these areas. This is a cross-sectional study, using the data of victims attended in three emergency hospitals in Belo Horizonte-Brazil between January 2008 and December 2010. Based on the process of spatial signature, the socio-spatial condition of the victims was identified according to data from census tracts. The spatial distribution trends of the addresses of victims were analyzed using Kernel maps and Ripley’s K function. Multicriteria analysis was used to analyze the territorial insertion of victims, using a combination of variables to obtain the degree of socio-spatial vulnerability. The residences of the victims were distributed in an aggregated manner in urban areas, with a confidence level of 99%. The highest densities were found in areas of unfavorable socioeconomic conditions and, to a lesser extent, areas with worse residential and neighborhood infrastructure. Spatial clusters of households formed in slums with a significant level of socio-spatial vulnerability. Explanations of the living conditions in segregated urban areas and analysis of the concentration of more vulnerable populations should be a priority in the development of public health and safety policies. 相似文献