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71.
Nikolaou PD Papoutsis II Atta-Politou J Athanaselis SA Spiliopoulou CA Calokerinos AC Maravelias CP 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,867(2):219-225
A sensitive and specific GC/MS method for the determination of methadone (MDN) and its two main metabolites, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and 2-ethyl-5-methyl-3,3-diphenylpyrroline (EMDP), in plasma samples obtained from venous and arterial umbilical cord blood and maternal blood has been developed, optimized and validated. Specimen preparation includes protein precipitation with acetonitrile and simultaneous solid-phase extraction of the three analytes. Methadone-d9 was used as internal standard for the determination of MDN and EMDP, while EDDP-d3 for EDDP. Limits of detection were 0.6 microg/L for MDN and 0.3 microg/L for EDDP and EMDP, while limits of quantification were 2.0 microg/L for MDN and 1.0 microg/L for EDDP and EMDP. The calibration curves were linear up to 2000 microg/L for MDN and up to 1000 microg/L for EDDP and EMDP. Absolute recovery ranged from 94.8 to 99.7% for all three analytes. Intra- and interday accuracy was less than 5.3 and 5.5%, respectively, while intra- and interday precision was less than 3.5 and 5.0%, correspondingly, for all analytes. The method proved suitable for the determination of MDN and its two main metabolites in plasma samples obtained from umbilical cord and maternal blood of a woman participating in a MDN maintenance program, during the prenatal and postpartum period. 相似文献
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Veronica Alfieri Marina Aiello Roberta Pisi Panagiota Tzani Elisa Mariani Emilio Marangio Dario Olivieri Gabriele Nicolini Alfredo Chetta 《Respiratory research》2014,15(1)
Background
We investigated whether a relationship between small airways dysfunction and bronchial hyperresponsiveness (BHR), expressed both in terms of ease of airway narrowing and of excessive bronchoconstriction, could be demonstrated in asthma.Methods
63 (36 F; mean age 42 yr ± 14) stable, mild-to-moderate asthmatic patients (FEV1 92% pred ±14; FEV1/FVC 75% ± 8) underwent the methacholine challenge test (MCT). The degree of BHR was expressed as PD20 (in μg) and as ∆FVC%. Peripheral airway resistance was measured pre- and post-MCT by impulse oscillometry system (IOS) and expressed as R5-R20 (in kPa sL−1).Results
All patients showed BHR to methacholine (PD20 < 1600 μg) with a PD20 geometric (95% CI) mean value of 181(132–249) μg and a ∆FVC% mean value of 13.6% ± 5.1, ranging 2.5 to 29.5%. 30 out of 63 patients had R5-R20 > 0.03 kPa sL−1 (>upper normal limit) and showed ∆FVC%, but not PD20 values significantly different from the 33 patients who had R5-R20 ≤ 0.03 kPa sL−1 (15.8% ± 4.6 vs 11.5% ± 4.8, p < 0.01 and 156(96–254) μg vs 207 (134–322) μg, p = 0.382). In addition, ∆FVC% values were significantly related to the corresponding pre- (r = 0.451, p < 0.001) and post-MCT (r = 0.376, p < 0.01) R5-R20 values.Conclusions
Our results show that in asthmatic patients, small airway dysfunction, as assessed by IOS, is strictly associated to BHR, expressed as excessive bronchoconstriction, but not as ease of airway narrowing. 相似文献76.
Espiña B Cagide E Louzao MC Fernandez MM Vieytes MR Katikou P Villar A Jaen D Maman L Botana LM 《Bioscience reports》2009,29(1):13-23
Palytoxin is one of the most complex and biggest molecules known to show extreme acute toxicity. The dinoflagellate Ostreopsis spp., the producer organism of palytoxin, has been shown to be distributed worldwide, thus making palytoxin an emerging toxin. Rat-derived hepatocytes (Clone 9) and BE (2)-M17 human neuroblastoma cells were used to test palytoxin or palytoxin-like compounds by measuring the cell metabolic rate with Alamar Blue. The dose-dependent decrease in viability was specifically inhibited by ouabain in the case of BE (2)-M17 neuroblastoma cells. This is a functional, dynamic and simple test for palytoxins with high sensitivity (as low as 0.2 ng/ml). This method was useful for toxin detection in Ostreopsis extracts and naturally contaminated mussel samples. A comparative study testing toxic mussel extracts by LC (liquid chromatography)-MS/MS (tandem MS), MBA (mouse bioassay), haemolysis neutralization assay and a cytotoxicity test indicated that our method is suitable for the routine determination and monitoring of palytoxins and palytoxin-like compounds. 相似文献
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Konstantina Katsarou Elisavet Serti Panagiota Tsitoura Alexandros A. Lavdas Agoritsa Varaklioti Angela-Maria Pickl-Herk Dieter Blaas Devrim Oz-Arslan Rong Zhu Peter Hinterdorfer Penelope Mavromara Urania Georgopoulou 《Biochimie》2009
Circulating ‘free’ non-enveloped Hepatitis C virus (HCV) core protein has been demonstrated in HCV-infected patients, and HCV subgenomes with deletions of the envelope proteins have been previously identified. Initial studies from our laboratory, previously published, indicated that expression of HCV core in insect cells can direct the formation of capsid-like particles lacking the envelope glycoproteins. These protein nanospheres, morphologically similar to natural capsids, were shown to be taken up by human hepatic cells and to produce cell-signalling events. To follow the intracellular fate of these particles we fused the core protein to eGFP. We demonstrate that the chimeric proteins core173-eGFP, eGFP-core191 and eGFP-core173 can be efficiently expressed, self-assembled, and form fluorescent non-enveloped capsid-like particles. By using confocal microscopy and FACS analysis, we provide evidence that the fluorescent nanospheres can not only enter human hepatic cells – the main target of HCV – but also human immune cells such as T and B lymphocytes, as well as human myeloid leukaemia cells differentiated along the monocyte/macrophage-like pathway. The fluorescent particles might thus be used to trace the intracellular trafficking of naked HCV capsids as showed by live microscopy and to further understand their biological significance. 相似文献
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Athanasia Mouzaki Ioannis Panagoulias Zoe Dervilli Vassiliki Zolota Panagiota Spadidea Maria Rodi Fotios P. Panitsas Eleni Lagadinou Anne-Lise de Lastic Tassos Georgakopoulos 《Cytokine》2009,48(3):203-211
Several studies have implicated leptin in the pathophysiology of neoplasias. We investigated the direct effect of leptin on malignant hematopoietic tissue that included: primary acute myeloid leukemia (AML) cells, leukemic cell lines and bone marrow biopsies from multiple myeloma (MM) patients. PBMC, T-cells, B-cells and monocytes from healthy subjects served as controls. We defined the patterns of OB-R isoform expression in AML cells and leukemic cell lines in comparison to control cells by RT-PCR. rLeptin upregulated the expression of OB-R and endogenous leptin in AML blasts and certain cell lines but not in control cells. Cytometric Bead Array analysis of pro- and anti-inflammatory cytokines showed that rleptin upregulates IL-6 secretion by AML cells, various cytokines by the leukemic cell lines tested and IL-10 secretion by control PBMC, contributed by monocytes. Western immunoblotting revealed that the effect of rleptin was independent of JAK-2/phospho-JAK-2 protein levels. Finally, MM biopsies stained positive for leptin and, to a lesser extend, OB-R. Immunoreactivity was confined mostly to the nucleus of the myeloma cells. Normal myelocytes, promyelocytes and megakaryocytes stained weakly positive, and erythroid cells were constantly negative. We propose that the leptin/OB-R system is strongly and directly involved in supporting the growth of hematopoietic malignancies. 相似文献
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Panagiota G Stathopoulou Johnah C Galicia Manjunatha R Benakanakere Carlos A Garcia Jan Potempa Denis F Kinane 《BMC microbiology》2009,9(1):107-12