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61.
Xue-Qing Wang Glenn F Evans M Leticia Alfaro Steven H Zuckerman 《Biochemical and biophysical research communications》2002,290(3):891-897
CD9, a member of the tetraspanin family is a cell surface marker expressed on myeloid and nonmyeloid as well as on neoplastic cells. The present study has focused on the role of inflammation and macrophage activation in the regulation of CD9 expression. We report that the expression of CD9 on primary cultures of murine peritoneal macrophages was down regulated by Interferon-gamma, IFN-gamma. This down regulation was concentration-dependent and maximal by 48 h. The changes in surface expression were consistent with similar reductions in CD9 protein and message levels by Western and Northern blot analyses. The mechanism by which IFN-gamma decreases CD9 expression appears to be through the Stat1 signaling pathway as Stat1 knockout mice did not demonstrate any reduction in CD9 expression by IFN-gamma treatment. These results represent the first evidence for the down regulation of CD9 expression with macrophage activation. 相似文献
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63.
Leticia Ruiz Garcia Consuelo Díaz de la Guardia Juan Francisco Mota 《Aerobiologia》1998,14(2-3):281-284
The first results are presented of an aerobiological analysis of the atmosphere of the town of Almería, carried out between
November 1995 and October 1996. A Lanzoni volumetric spore trap was used for sample collection. The composition and seasonal
evolution of the pollen spectrum were determined over a 1-year period in relation to the vegetation and climatic conditions
of the study area. Twenty-six pollen types were identified as accounting for >0.05% of the total pollen collected. The main
sources of airborne pollen were Palmae (17.76%),Olea (16.10%), Chenopodiaceae/Amaranthaceae (13.99%), Urticaceae (10.18%) and Poaceae (8.64%). The annual pollen variation presented
a period of maximum emission from March to June, with a subsequent, less intensive period from August to November. The minimum
pollen values were obtained from December to February. The highest concentrations occurred in May, which was also the month
which presented the highest pollen diversity, whereas the lowest values were observed in January. 相似文献
64.
Canto-Canché B Guillén-Maldonado DK Peraza-Echeverría L Conde-Ferráez L James-Kay A 《Molecular biotechnology》2007,36(1):64-70
A bacterial artificial chromosome library of the causal agent of the Black Sigatoka leaf spot disease of banana and plantain,
Mycosphaerella fijiensis, has been constructed using a non-sphaeroplasting technique and characterized using both homologous and heterologous probes.
After first and a second size selection of PFGE-fractionated DNA, a ligation was obtained using a 1:4 molar ratio (insert:vector).
One hundred random clones were analyzed, and the mean insert size was estimated to be 90 kb. The range of the insert sizes
was between 40 and 160 kb. The highest percentage of inserts belonged to the range between 80 and 100 kb; 32% of the inserts
had 2 or 3 internal NotI sites. This library consists of 1920 clones, if the genomic size is at least 35 Mb, then this represents 4.9× genome equivalents,
which was supported by hybridization results with homologous and heterologous probes.
Blondy Canto-Canché and Diana Karina Guillén-Maldonado contributed equally to this work and should be regarded as co-first
authors. 相似文献
65.
Moritz Menzel Diana Meckbach Benjamin Weide Nora C. Toussaint Karin Schilbach Seema Noor Thomas Eigentler Kristian Ikenberg Christian Busch Leticia Quintanilla‐Martinez Ursula Kohlhofer Antonia Göke Friederike Göke Rupert Handgretinger Christian Ottmann Boris C. Bastian Claus Garbe Martin Röcken Sven Perner Oliver Kohlbacher Jürgen Bauer 《Pigment cell & melanoma research》2014,27(4):671-673
66.
Giulliana T. Almeida Regina C. G. Lage Leticia Anderson Thiago M. Venancio Helder I. Nakaya Patrícia A. Miyasato Henrique K. Rofatto Adhemar Zerlotini Eliana Nakano Guilherme Oliveira Sergio Verjovski-Almeida 《PLoS neglected tropical diseases》2015,9(9)
BackgroundTreatment and morbidity control of schistosomiasis relies on a single drug, praziquantel (PZQ), and the selection of resistant worms under repeated treatment is a concern. Therefore, there is a pressing need to understand the molecular effects of PZQ on schistosomes and to investigate alternative or synergistic drugs against schistosomiasis.MethodologyWe used a custom-designed Schistosoma mansoni expression microarray to explore the effects of sublethal doses of PZQ on large-scale gene expression of adult paired males and females and unpaired mature females. We also assessed the efficacy of PZQ, omeprazole (OMP) or their combination against S. mansoni adult worms with a survival in vitro assay.ConclusionsFunctional analysis of gene interaction networks is an important approach that can point to possible novel synergistic drug candidates. We demonstrated the potential of this strategy by showing that PZQ in combination with OMP displayed increased efficiency against S. mansoni adult worms in vitro when compared with either drug alone. 相似文献
67.
Nata?a Anastasov Margit Klier Ina Koch Daniela Angermeier Heinz H?fler Falko Fend Leticia Quintanilla-Martinez 《Journal of Hematopathology》2009,2(1):9-19
RNA interference is a powerful tool for the functional analysis of proteins by specific gene knockdown. In this study, we devised a rapid and efficient way to screen suitable siRNA sequences and subsequently employ them for specific gene knockdown in usually hard-to-transfect lymphoid cell lines, using a self-inactivating lentiviral vector. Two proteins with different half-lives were chosen, cyclin D1 and STAT3. A specific lacZ reporter fusion assay was used to identify highly effective siRNA sequences. Only siRNA molecules with more than 85% of knockdown efficiency were selected for the generation of lentiviral transfer vectors. Transduction rates of 75–99% were achieved in the lymphoma cell lines Granta 519 (mantle cell lymphoma), Karpas 299, and SUDHL-1 (anaplastic large T cell lymphoma), as demonstrated by green fluorescent protein expression in fluorescence-activated cell sorting analysis. The high level of transduction efficiency allows RNA interference studies to be performed on transduced cells without further manipulation, such as cell sorting or cloning. The LacZ reporter system together with the lentivirus technology is a very important tool in the hematology field, which enables experiments in lymphoid cells that were not possible before.
Electronic supplementary material
The online version of this article (doi:10.1007/s12308-008-0020-x) contains supplementary material, which is available to authorized users. 相似文献68.
The objectives of this work were to isolate the microorganisms responsible for a previously observed degradation of polycyclic
aromatic hydrocarbons (PAH) in soil and to test a method for cleaning a PAH-contaminated soil. An efficient PAH degrader was
isolated from an agricultural soil and designated as Mycobacterium LP1. In liquid culture, it degraded phenanthrene (58%), pyrene (24%), anthracene (21%) and benzo(a)pyrene (10%) present in mixture (initial concentration 50 μg ml−1 each) and phenanthrene (92%) and pyrene (94%) as sole carbon sources after 14 days of incubation at 30°C. In soil, Mycobacterium LP1 mineralised 14C-phenanthrene (45%) and 14C-pyrene (65%) after 10 days. The good ability of this Mycobacterium was combined with the benzo(a)pyrene oxidation effect obtained by 1% w/w rapeseed oil in a sequential treatment of a PAH-spiked soil (total PAH concentration
200 mg kg−1). The first step was incubation with the bacterium for 12 days and the second step was the addition of the rapeseed oil after
this time and a further incubation of 22 days. Phenanthrene (99%), pyrene (95%) and anthracene (99%) were mainly degraded
in the first 12 days and a total of 85% of benzo(a)pyrene was transformed during the whole process. The feasibility of the method is discussed. 相似文献
69.
70.
Eliane Volchan Isabel A. David Gisella Tavares Billy M. Nascimento Jose M. Oliveira Sonia Gleiser Andre Szklo Cristina Perez Tania Cavalcante Mirtes G. Pereira Leticia Oliveira 《PloS one》2013,8(8)