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141.
Unicapsula marquesi n. sp. (Myxosporea) is described from gill filaments of Polydactylus quadrifilis (Pisces, Polynemidae) obtained from coats of Senegal. The cysts were elongated and their length was 1 to 3 mm. The spores were pyramidal and composed of three valves. Only one of theses valves contained a developed polar capsule measuring 3.01 +/- 0.09 microns in diameter. Length of spore was 6.13 +/- 0.21 microns and the width was 7.18 +/- 0.17. No filament like appendage at the extremity of shell valves. Data on ultrastructure of spores are presented. 相似文献
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143.
Terenius O Lindh JM Eriksson-Gonzales K Bussière L Laugen AT Bergquist H Titanji K Faye I 《FEMS microbiology ecology》2012,80(3):556-565
In vector mosquitoes, the presence of midgut bacteria may affect the ability to transmit pathogens. We have used a laboratory colony of Aedes aegypti as a model for bacterial interspecies competition and show that after a blood meal, the number of species (culturable on Luria-Bertani agar) that coexist in the midgut is low and that about 40% of the females do not harbor any cultivable bacteria. We isolated species belonging to the genera Bacillus, Elizabethkingia, Enterococcus, Klebsiella, Pantoea, Serratia, and Sphingomonas, and we also determined their growth rates, antibiotic resistance, and ex vivo inhibition of each other. To investigate the possible existence of coadaptation between midgut bacteria and their host, we fed Ae.?aegypti cohorts with gut bacteria from human, a frog, and two mosquito species and followed the bacterial population growth over time. The dynamics of the different species suggests coadaptation between host and bacteria, and interestingly, we found that Pantoea stewartii isolated from Ae.?aegypti survive better in Ae.?aegypti as compared to P.?stewartii isolated from the malaria mosquito Anopheles gambiae. 相似文献
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Badara Cisse Matthew Cairns Ernest Faye Ousmane NDiaye Babacar Faye Cecile Cames Yue Cheng Maguette NDiaye Aminata Collé L? Kirsten Simondon Jean-Francois Trape Oumar Faye Jean Louis NDiaye Oumar Gaye Brian Greenwood Paul Milligan 《PloS one》2009,4(9)
Background
The long terminal half life of piperaquine makes it suitable for intermittent preventive treatment for malaria but no studies of its use for prevention have been done in Africa. We did a cluster randomized trial to determine whether piperaquine in combination with either dihydroartemisin (DHA) or sulfadoxine-pyrimethamine (SP) is as effective, and better tolerated, than SP plus amodiaquine (AQ), when used for intermittent preventive treatment in children delivered by community health workers in a rural area of Senegal.Methods
Treatments were delivered to children 3–59 months of age in their homes once per month during the transmission season by community health workers. 33 health workers, each covering about 60 children, were randomized to deliver either SP+AQ, DHA+PQ or SP+PQ. Primary endpoints were the incidence of attacks of clinical malaria, and the incidence of adverse events.Results
1893 children were enrolled. Coverage of monthly rounds and compliance with daily doses was similar in all groups; 90% of children received at least 2 monthly doses. Piperaquine combinations were better tolerated than SP+AQ with a significantly lower risk of common, mild adverse events. 103 episodes of clinical malaria were recorded during the course of the trial. 68 children had malaria with parasitaemia >3000/µL, 29/671 (4.3%) in the SP+AQ group, compared with 22/604 (3.6%) in the DHA+PQ group (risk difference 0.47%, 95%CI −2.3%,+3.3%), and 17/618 (2.8%) in the SP+PQ group (risk difference 1.2%, 95%CI −1.3%,+3.6%). Prevalences of parasitaemia and the proportion of children carrying Pfdhfr and Pfdhps mutations associated with resistance to SP were very low in all groups at the end of the transmission season.Conclusions
Seasonal IPT with SP+PQ in children is highly effective and well tolerated; the combination of two long-acting drugs is likely to impede the emergence of resistant parasites.Trial Registration
ClinicalTrials.gov NCT00529620相似文献146.
Fabiano Oliveira Seydou Doumbia Jennifer M. Anderson Ousmane Faye Souleymane S. Diarra Pierre Traoré Moumine Cisse Guimba Camara Koureissi Tall Cheick A. Coulibaly Sibiry Samake Ibrahim Sissoko Bourama Traoré Daouda Diallo Somita Keita Rick M. Fairhurst Jesus G. Valenzuela Shaden Kamhawi 《PLoS neglected tropical diseases》2009,3(12)
Apart from a single report, the last publication of cutaneous leishmaniasis (CL) in Mali dates back more than 20 years. The absence of information on the current status of CL in Mali led us to conduct a cohort study in Kemena and Sougoula, two villages in Central Mali from which cases of CL have been recently diagnosed by Mali''s reference dermatology center in Bamako. In May 2006, we determined the baseline prevalence of Leishmania infection in the two villages using the leishmanin skin test (LST). LST-negative individuals were then re-tested over two consecutive years to estimate the annual incidence of Leishmania infection. The prevalence of Leishmania infection was significantly higher in Kemena than in Sougoula (45.4% vs. 19.9%; OR: 3.36, CI: 2.66–4.18). The annual incidence of Leishmania infection was also significantly higher in Kemena (18.5% and 17% for 2007 and 2008, respectively) than in Sougoula (5.7% for both years). These data demonstrate that the risk of Leishmania infection was stable in both villages and confirm the initial observation of a significantly higher risk of infection in Kemena (OR: 3.78; CI: 2.45–6.18 in 2007; and OR: 3.36; CI: 1.95–5.8 in 2008; P<0.005). The absence of spatial clustering of LST-positive individuals in both villages indicated that transmission may be occurring anywhere within the villages. Although Kemena and Sougoula are only 5 km apart and share epidemiologic characteristics such as stable transmission and random distribution of LST-positive individuals, they differ markedly in the prevalence and annual incidence of Leishmania infection. Here we establish ongoing transmission of Leishmania in Kemena and Sougoula, Central Mali, and are currently investigating the underlying factors that may be responsible for the discrepant infection rates we observed between them.
Trial Registration
ClinicalTrials.gov NCT00344084相似文献147.
Meriem Benchabane Claude Saint‐Jore‐Dupas Loïc Faye Véronique Gomord Dominique Michaud 《Plant biotechnology journal》2009,7(2):161-171
Recently, we have observed a nuclear localization for human α1‐antichymotrypsin (AACT) expressed in the cytosol of transgenic Bright Yellow‐2 (BY‐2) tobacco cultured cells (see accompanying paper: Benchabane, M., Saint‐Jore‐Dupas, C., Bardor, M., Faye, L., Michaud, D. and Gomord, V. (2008a) Targeting and post‐translational processing of human α1‐antichymotrypsin in BY‐2 tobacco cultured cells. Plant Biotechnol. J. doi: 10.1111/j.1467‐7652.2008.00382.x). In the present article, we assess whether the intrinsic DNA‐binding activity of AACT can explain its nuclear localization, and whether this same activity has an impact on its protease inhibitory potency and stability in planta. An engineered form of AACT with no DNA‐binding activity, rAACTΔK, was compared with the wild‐type polypeptide, rAACT, in terms of chymotrypsin inhibitory potency, stability in planta and distribution in tobacco cells. In accordance with available data reporting distinct sites for protease inhibition and DNA binding, rAACT and rAACTΔK showed similar antichymotrypsin activity, similar to the activity of native AACT purified from human plasma. As observed for AACT in BY‐2 tobacco cells, a green fluorescent protein (GFP)‐AACT fusion transiently expressed in the cytosol of tobacco leaf epidermal cells was detected mainly in the nucleus by confocal laser microscopy. By contrast, rAACTΔK expressed as a GFP fusion showed a balanced distribution between the cytosol and the nucleus, similar to the distribution pattern of free GFP exhibiting no DNA‐binding affinity. In line with immunodetection data showing higher accumulation levels for GFP‐AACT in tobacco leaf cells, rAACTΔK was more susceptible than rAACT to tryptic digestion in the presence of DNA. Overall, these observations suggest the following: (i) a retention effect of DNA on AACT in the nucleus; and (ii) a stabilizing effect of the AACT–DNA interaction on rAACT challenged with non‐target proteases, which, possibly, may be useful in protecting this protein in plant expression platforms. 相似文献
148.
149.
Ryan P. Wurz Liping H. Pettus Bradley Henkle Lisa Sherman Matthew Plant Kent Miner Helen J. McBride Lu Min Wong Christiaan J.M. Saris Matthew R. Lee Samer Chmait Christopher Mohr Faye Hsieh Andrew S. Tasker 《Bioorganic & medicinal chemistry letters》2010,20(5):1680-1684
A novel class of pyrazolopyridazine p38α mitogen-activated protein kinase (MAPK) inhibitors is disclosed. A structure activity relationship (SAR) investigation was conducted driven by the ability of these compounds to inhibit the p38α enzyme, the secretion of TNFα in a LPS-challenged THP1 cell line and TNFα-induced production of IL-8 in the presence of 50% human whole blood (hWB). This study resulted in the discovery of several inhibitors with IC50 values in the single-digit nanomolar range in hWB. Further investigation of the pharmacokinetic profiles of these lead compounds led to the identification of three potent and orally bioavailable p38α inhibitors 2h, 2m, and 13h. Inhibitor 2m was found to be highly selective for p38α/β over a panel of 402 other kinases in Ambit screening, and was highly efficacious in vivo in the inhibition of TNFα production in LPS-stimulated Lewis rats with an ED50 of ca. 0.08 mg/kg. 相似文献
150.
N-Glycosylation of a mouse IgG expressed in transgenic tobacco plants 总被引:11,自引:0,他引:11
Cabanes-Macheteau M Fitchette-Lainé AC Loutelier-Bourhis C Lange C Vine ND Ma JK Lerouge P Faye L 《Glycobiology》1999,9(4):365-372
Since plants are emerging as an important system for the expression of recombinant glycoproteins, especially those intended for therapeutic purposes, it is important to scrutinize to what extent glycans harbored by mammalian glycoproteins produced in transgenic plants differ from their natural counterpart. We report here the first detailed analysis of the glycosylation of a functional mammalian glycoprotein expressed in a transgenic plant. The structures of the N-linked glycans attached to the heavy chains of the monoclonal antibody Guy's 13 produced in transgenic tobacco plants (plantibody Guy's 13) were identified and compared to those found in the corresponding IgG1 of murine origin. Both N-glycosylation sites located on the heavy chain of the plantibody Guy's 13 are N-glycosylated as in mouse. However, the number of Guy's 13 glycoforms is higher in the plant than in the mammalian expression system. Despite the high structural diversity of the plantibody N-glycans, glycosylation appears to be sufficient for the production of a soluble and biologically active IgG in the plant system. In addition to high-mannose-type N-glycans, 60% of the oligosaccharides N-linked to the plantibody have beta(1, 2)-xylose and alpha(1, 3)-fucose residues linked to the core Man3GlcNAc2. These plant-specific oligosaccharide structures are not a limitation to the use of plantibody Guy's 13 for topical immunotherapy. However, their immunogenicity may raise concerns for systemic applications of plantibodies in human. 相似文献