Interlaboratory Evaluation Of Two Reverse-Transcriptase Polymeric Chain Reaction-Based Methods For Detection Of Four Fruit Tree VirusesMassart, Sébastien ; Brostaux, Yves ; et alin Annals of Applied Biology (2009), 154(1), 133-141 Detailed reference viewed: 30 (5 ULg) Interlaboratory studies on two high-performance liquid chromatographic assays for tylosin (tartrate); ; et al in Journal of Chromatography. A (1999), 830(1), 3-28 An interlaboratory study was performed on two high-performance liquid chromatographic methods to determine tylosin. The first method is a reversed-phase HPLC on a C-18 column, while the second is a method ... [more ▼] An interlaboratory study was performed on two high-performance liquid chromatographic methods to determine tylosin. The first method is a reversed-phase HPLC on a C-18 column, while the second is a method using a polymeric stationary phase. The first method is described in several pharmacopoeia monographs on tylosin, to determine the composition of a tylosin mixture, while the second method is recently proposed to determine both the composition and the contents in such a mixture. The interlaboratory studies were set-up and interpreted according to ISO guidelines. This paper is written as a tutorial type of article explaining the principles and methods of these guidelines. The results of both methods were compared. Both were found to have disadvantages but in general the old method is still preferred, both for composition determination and to assay the components. (C) 1999 Elsevier Science B.V. All rights reserved. [less ▲] Detailed reference viewed: 30 (3 ULg) Interlaboratory study of a liquid chromatography method for erythromycin: determination of uncertainty.; ; et al in Journal of Chromatography. A (2003), 1010(1), 63-74 Erythromycin is a mixture of macrolide antibiotics produced by Saccharopolyspora erythreas during fermentation. A new method for the analysis of erythromycin by liquid chromatography has previously been ... [more ▼] Erythromycin is a mixture of macrolide antibiotics produced by Saccharopolyspora erythreas during fermentation. A new method for the analysis of erythromycin by liquid chromatography has previously been developed. It makes use of an Astec C18 polymeric column. After validation in one laboratory, the method was now validated in an interlaboratory study. Validation studies are commonly used to test the fitness of the analytical method prior to its use for routine quality testing. The data derived in the interlaboratory study can be used to make an uncertainty statement as well. The relationship between validation and uncertainty statement is not clear for many analysts and there is a need to show how the existing data, derived during validation, can be used in practice. Eight laboratories participated in this interlaboratory study. The set-up allowed the determination of the repeatability variance, s(2)r and the between-laboratory variance, s(2)L. Combination of s(2)r and s(2)L results in the reproducibility variance s(2)R. It has been shown how these data can be used in future by a single laboratory that wants to make an uncertainty statement concerning the same analysis. [less ▲] Detailed reference viewed: 35 (3 ULg) Interlaboratory study of a NACE method for the determination of R-timolol content in S-timolol maleate: assessment of uncertainty.Marini Djang'Eing'A, Roland ; ; et alin Electrophoresis (2006), 27(12), 2386-99 Analyses of statistical variance were applied to evaluate the precision and practicality of a CD-based NACE assay for R-timolol after enantiomeric separation of R- and S-timolol. Data were collected in an ... [more ▼] Analyses of statistical variance were applied to evaluate the precision and practicality of a CD-based NACE assay for R-timolol after enantiomeric separation of R- and S-timolol. Data were collected in an interlaboratory study by 11 participating laboratories located in Europe and North America. General qualitative method performance was examined using suitability descriptors (i.e. resolution, selectivity, migration times and S/N), while precision was determined by quantification of variances in the determination of R-timolol at four different impurity levels in S-timolol maleate samples. The interlaboratory trials were designed in accordance with the ISO guideline 5725-2. This allowed estimating for each sample, the different variances, i.e. between-laboratory (s2(Laboratories)), between-day (s2(Days)) and between-replicate (s2(Replicates)). The variances of repeatability (s2r) and reproducibility (s2R) were then calculated. The estimated uncertainty, derived from the precision estimates, seems to be concentration-dependent above a given threshold. This example of R-timolol illustrates how a laboratory can evaluate uncertainty in general. [less ▲] Detailed reference viewed: 56 (12 ULg)![]() Interleukin-1 Beta Induces Nuclear Factor Kappa B in Epithelial Cells Independently of the Production of Reactive Oxygen Intermediates; Dejardin, Emmanuel ; et alin European Journal of Biochemistry (1996), 242(3), 544-9 A large body of work has been devoted to tumor necrosis factor alpha or interleukin-1 beta (IL-1 beta) signaling leading to the activation of the transcription factor nuclear factor-kappa B (NF-kappa B ... [more ▼] A large body of work has been devoted to tumor necrosis factor alpha or interleukin-1 beta (IL-1 beta) signaling leading to the activation of the transcription factor nuclear factor-kappa B (NF-kappa B) in various cell types. Several studies have indicated that NF-kappa B activation depends strictly on the production of reactive oxygen intermediates. In this report, we first demonstrated that IL-1 beta is a potent activator of NF-kappa B in various epithelial transformed cell lines (OVCAR-3, SKOV-3, MCF7 A/Z). In these cells, IL-1 beta rapidly induces NF-kappa B through a complete degradation of I kappa B-alpha, while H2O2 activates NF-kappa B with slower kinetics through a partial degradation of I kappa B-alpha, p100 and p105. We showed that IL-1 beta-mediated induction of NF-kappa B in OVCAR-3 and in other epithelial cell lines does not proceed through the production of reactive oxygen intermediates, while the same cytokine activates NF-kappa B in lymphoid cells through the intracellular generation of H2O2. Our study demonstrated that several signaling pathways lead to the activation of NF-kappa B, following IL-1 beta treatment in different cell types. [less ▲] Detailed reference viewed: 34 (0 ULg) Interleukin-1, Interleukin-6 and Oncostatin M Stimulate Normal Subchondral Osteoblasts to Induce Cartilage DegradationSanchez, Christelle ; Deberg, Michelle ; et alPoster (2005) Detailed reference viewed: 5 (0 ULg) Interleukin-1, Interleukin-6 and Oncostatin M Stimulate Normal Subchondral Osteoblasts to Induce Cartilage DegradationSanchez, Christelle ; Deberg, Michelle ; et alin Osteoporosis International (2005), 16(Suppl 3), 54-55 Detailed reference viewed: 11 (3 ULg) Interleukin-1, interleukin-6 and oncostatin M stimulate normal subchondral osteoblasts to induce cartilage degradationSanchez, Christelle ; Deberg, Michelle ; et alin Osteoarthritis and Cartilage (2004), 12(Suppl. B), 98 Detailed reference viewed: 7 (2 ULg) Interleukin-1beta and interleukin-6 disturb the antioxidant enzyme system in bovine chondrocytes: a possible explanation for oxidative stress generationMathy, Marianne ; ; Sanchez, Christelle et alPoster (2006) Detailed reference viewed: 9 (0 ULg) Interleukin-1beta and interleukin-6 disturb the antioxidant enzyme system in bovine chondrocytes: a possible explanation for oxidative stress generationMathy, Marianne ; ; Sanchez, Christelle et alin Osteoarthritis and Cartilage (2006), 14(Suppl B), 80 Detailed reference viewed: 15 (2 ULg) Interleukin-1beta and Interleukin-6 Disturb the Antioxidant Enzyme System in Bovine Chondrocytes: A Possible Explanation for Oxidative Stress GenerationMathy, Marianne ; Hogge, Laurence ; Sanchez, Christelle et alin Osteoarthritis and Cartilage (2008), 16 OBJECTIVE: Beside matrix metalloproteinases, reactive oxygen species (ROS) are the main biochemical factors of cartilage degradation. To prevent ROS toxicity, chondrocytes possess a well-coordinated ... [more ▼] OBJECTIVE: Beside matrix metalloproteinases, reactive oxygen species (ROS) are the main biochemical factors of cartilage degradation. To prevent ROS toxicity, chondrocytes possess a well-coordinated enzymatic antioxidant system formed principally by superoxide dismutases (SODs), catalase (CAT) and glutathione peroxidase (GPX). This work was designed to assess the effects of interleukin (IL)-1beta and IL-6 on the enzymatic activity and gene expression of SODs, CAT and GPX in bovine chondrocytes. METHODS: Bovine chondrocytes were cultured in monolayer for 4-96h in the absence or in the presence of IL-1beta (0.018-1.8ng/ml) or IL-6 (10-100ng/ml). To study signal transduction pathway, inhibitors of mitogen-activated protein kinases (MAPK) (PD98059, SB203580 and SP600125) (5-20muM) and nuclear factor (NF)-kappaB inhibitors [BAY11-7082 (1-10muM) and MG132 (0.1-10muM)] were used. SODs, CAT and GPX enzymatic activities were evaluated in cellular extract by using colorimetric enzymatic assays. Mn SODs, Cu/Zn SOD, extracellular SOD (EC SOD), CAT and GPX gene expressions were quantified by real-time and quantitative polymerase chain reaction (PCR). RESULTS: Mn SOD and GPX activities were dose and time-dependently increased by IL-1beta. In parallel, IL-1beta markedly enhanced Mn SOD and GPX gene expressions, but decreased Cu/Zn SOD, EC SOD and CAT gene expressions. Induction of SOD enzymatic activity and Mn SOD mRNA expression were inhibited by NF-kappaB inhibitors but not by MAPK inhibitors. IL-6 effects were similar but weaker than those of IL-1beta. CONCLUSIONS: In conclusion, IL-1beta, and to a lesser extend IL-6, dysregulates enzymatic antioxidant defenses in chondrocyte. These changes could lead to a transient accumulation of H(2)O(2) in mitochondria, and consequently to mitochondria damage. These changes contribute to explain the mitochondrial dysfunction observed in osteoarthritis chondrocytes. [less ▲] Detailed reference viewed: 44 (4 ULg) Interleukin-1beta and tumor necrosis factor-alpha enhance the shedding of Interleukin-6 receptor in osteoblastic cells: Involvement of tumor necrosis factor-alpha converting enzyme; ; Ribbens, Clio et alin Arthritis and Rheumatism (2003, September), 48(9, Suppl. S), 482 Detailed reference viewed: 16 (1 ULg) Interleukin-32 expression is associated with a poorer prognosis in head and neck squamous cell carcinoma.; Mouallif, Mustapha ; Hubert, Pascale et alin Molecular Carcinogenesis (2013) Head and neck squamous cell carcinoma (HNSCC) represent the sixth most common malignancy diagnosed worldwide. Patient's survival is low due the high frequency of tumor recurrence. Inflammation promotes ... [more ▼] Head and neck squamous cell carcinoma (HNSCC) represent the sixth most common malignancy diagnosed worldwide. Patient's survival is low due the high frequency of tumor recurrence. Inflammation promotes carcinogenesis as well as the formation of metastasis. Indeed, proinflammatory mediators are known to stimulate the expression of specific transcription factors such as Snai1 and to increase the ability of tumor cells to migrate into distant organs. The atypical interleukin-32 (IL32) was mainly described to exacerbate inflammatory responses in rheumatoid arthritis and inflammatory bowel diseases. IL32 is expressed in various cancers but its role in HNSCC physiology is still unexplored. Here, we analyzed the expression of IL32 and its implication on HNSCC aggressiveness. We showed that patients with tumor expressing high amounts of IL32 exhibit decreased disease-free periods (20.5 mo vs. 41 mo, P = 0.0041) and overall survival (P = 0.0359) in comparison with individuals with weak IL32 tumor expression. This overexpression was negatively correlated with gender (P = 0.0292) and p53 expression (P = 0.0307). In addition, in vitro data linked IL32 expression to metastasis formation since IL32 inhibition decreased Snai1 expression and tumor cell migration in a Boyden chamber assay. Our data provide new insight into the role of IL32 in HNSCC aggressiveness. (c) 2013 Wiley Periodicals, Inc. [less ▲] Detailed reference viewed: 17 (4 ULg) Interleukin-4-promoted T helper 2 responses enhance Nippostrongylus brasiliensis-induced pulmonary pathology.; ; et al in Infection and Immunity (2008), 76(12), 5535-42 The role of CD4(+) T-cell interleukin-4 (IL-4) receptor alpha (IL-4Ralpha) expression in T helper 2 (TH2) immune responses has not been defined. To examine this role, we infected CD4(+) T-cell IL-4Ralpha ... [more ▼] The role of CD4(+) T-cell interleukin-4 (IL-4) receptor alpha (IL-4Ralpha) expression in T helper 2 (TH2) immune responses has not been defined. To examine this role, we infected CD4(+) T-cell IL-4Ralpha knockout (KO) mice with the parasitic nematode Nippostrongylus brasiliensis, which induces strong host TH2 responses. Although N. brasiliensis expulsion was not affected in CD4(+) T-cell IL-4Ralpha KO mice, the associated lung pathology was reduced. Infected CD4(+) T-cell IL-4Ralpha KO mice showed abrogation of airway mucus production. Furthermore, CD4(+) T-cell IL-4Ralpha KO mouse lungs contained reduced numbers of lymphocytes and eosinophils. Restimulation of pulmonary region-associated T-cell populations showed that TH2 cytokine responses were disrupted. Secretion of IL-4, but not secretion of IL-13 or IL-5, from mediastinal lymph node CD4(+) T cells was reduced in infected CD4(+) T-cell IL-4Ralpha KO mice. Restimulation of tissue-derived CD4(+) T cells resulted in equivalent levels of IL-4 and IL-13 on day 7 postinfection (p.i.) in control and CD4(+) T-cell IL-4Ralpha KO mice. By day 10 p.i. the TH2 cytokine levels had significantly declined in CD4(+) T-cell IL-4Ralpha KO mice. Restimulation with N. brasiliensis antigen of total lung cell populations and populations with CD4(+) T cells depleted showed that CD4(+) T cells were a key TH2 cytokine source. These data demonstrated that CD4(+) T-cell IL-4 responsiveness facilitates eosinophil and lymphocyte recruitment, lymphocyte localization, and TH2 cytokine production in the allergic pathology associated with N. brasiliensis infections. [less ▲] Detailed reference viewed: 22 (1 ULg) Interleukin-6 and transforming growth factor-beta1 are increased in bronchoalveolar lavage fluid following thoracic radiotherapyBarthelemy, Nicole ; Bosquee, Léon ; Bartsch, Pierre et alin Lung Cancer (2003), 41(supp2), 173 Detailed reference viewed: 4 (1 ULg) Interleukin-6 mediates subchondral osteoblasts-induced cartilage degradationSanchez, Christelle ; ; et alin ICRS news letter (2006) Detailed reference viewed: 24 (0 ULg)![]() Interleukin-6 mediates subchondral osteoblasts-induced cartilage degradationSanchez, Christelle ![]() Conference (2006) Detailed reference viewed: 8 (0 ULg) Interleukin-6 mediates subchondral osteoblasts-induced cartilage degradationHenrotin, Yves ; ; Deberg, Michelle et alPoster (2005) Detailed reference viewed: 4 (0 ULg) Interleukin-6 mediates subchondral osteoblasts-induced cartilage degradationSanchez, Christelle ; ; Deberg, Michelle et alin Osteoarthritis and Cartilage (2005), 13(Suppl A), 157 Detailed reference viewed: 4 (1 ULg) Interleukin-6 mediates subchondral osteoblasts-induced cartilage degradationSanchez, Christelle ; ; Deberg, Michelle et alin Osteoporosis International (2006, March), 17(Suppl. 1), 53 Detailed reference viewed: 14 (3 ULg) |
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