Search results for "Matrix"
showing 10 items of 3205 documents
Evaluation of matrix solid-phase dispersion (MSPD) extraction for multi-mycotoxin determination in different flours using LC-MS/MS
2011
An existing matrix solid-phase dispersion (MSPD) method for aflatoxins (AFs) and ochratoxin A (OTA) extraction was extended by further 14 mycotoxins. After it careful optimization, this method was applied to determine the occurrence of these mycotoxins on commercial flour samples (with different cereals composition) collected from local markets. In a total of 49 samples investigated, 9 mycotoxins were identified. Nivalenol (NIV) and Beauvericin (BEA) were the mycotoxins found most frequently. The samples that presented major contamination were wheat flours and bakery preparations. Despite of the great number of positives finding, only one wheat flour sample exceeded the maximum limits (ML) …
Determination of ochratoxin A in organic and non-organic cereals and cereal products from Spain and Portugal
2008
The objective of this work was to know the occurrence of OTA in organic and non-organic cereals and cereal products from Spain and Portugal. A method based on extraction with matrix solid phase dispersion (MSPD) using octylsilica (C8) followed by liquid chromatography coupled with fluorescence detection (LC-FD) was used to determine OTA from the selected samples. Recoveries of OTA from the studied samples spiked at 10 ng/g level ranged from 78% to 89% with a standard deviation of 3.66. The limits of detection and quantification of this method were 0.05 and 0.19 ng/g, respectively. Furthermore, LC-FD after OTA methylation was used to confirm the identity of OTA in all positive samples. This …
Optimization of a decellularized protocol of porcine tracheas. Long-term effects of cryopreservation. A histological study
2021
[EN] Objective: The aim of this study was to optimize a decellularization protocol in the trachea of Sus scrofa domestica (pig) as well as to study the effects of long-term cryopreservation on the extracellular matrix of decellularized tracheas. Methods: Porcine tracheas were decellularized using Triton X-100, SDC, and SDS alone or in combination. The effect of these detergents on the extracellular matrix characteristics of decellularized porcine tracheas was evaluated at the histological, biomechanical, and biocompatibility level. Morphometric approaches were used to estimate the effect of detergents on the collagen and elastic fibers content as well as on the removal of chondrocytes from …
Microvesicles shed by oligodendroglioma cells and rheumatoid synovial fibroblasts contain aggrecanase activity
2012
Membrane microvesicle shedding is an active process and occurs in viable cells with no signs of apoptosis or necrosis. We report here that microvesicles shed by oligodendroglioma cells contain an ‘aggrecanase’ activity, cleaving aggrecan at sites previously identified as targets for adamalysin metalloproteinases with disintegrin and thrombospondin domains (ADAMTSs). Degradation was inhibited by EDTA, the metalloproteinase inhibitor GM6001 and by tissue inhibitor of metalloproteinases (TIMP)-3, but not by TIMP-1 or TIMP-2. This inhibitor profile indicates that the shed microvesicles contain aggrecanolytic ADAMTS(s) or related TIMP-3-sensitive metalloproteinase(s). The oligodendroglioma cells…
Serum proteome profiling of primary breast cancer indicates a specific biomarker profile.
2011
Non-invasive biomarkers for early breast cancer detection are urgently needed, as the risk of recurrent morbidity and mortality is closely related to the stage of the disease at the time of primary surgery. Currently, there are no established clinical biomarkers for breast cancer. Evaluation of protein expression patterns in body fluids using proteomic technologies can be used to discover new biomarkers for the detection of breast cancer. The aim of this study was to identify a biomarker signature identifying primary non-metastatic breast cancer and healthy controls. We screened 91 serum samples including 45 breast cancer patients and 46 healthy women using a proteomic approach. We found 14…
Zymographic detection and clinical correlations of MMP-2 and MMP-9 in breast cancer sera.
2004
Matrix metalloproteinases, in particular the gelatinases MMP-2 and MMP-9, have received great attention in recent years as putative tumour markers for clinical applications. The main reason for the observed interest is their easy detection in body fluids. Moreover, recent evidence has shown multiple functions of MMPs, rather than simply degrading ECM, which include the mobilisation of growth factors and processing of surface molecules. Several authors have reported increased levels of MMPs in a number of cancers, but clinical correlations in breast cancer are still fragmentary. Thus, the aim of the present research was to investigate the activity levels of circulating gelatinases in the ser…
Matrix metalloproteinase-1 is differentially expressed in signet ring cell, and intestinal colorectal carcinomas histotypes
2007
14564 Background: Signet ring cell colorectal carcinoma ( SRCC) pure is an infrequent and highly malignant variant of colorectal cancer, while this histological component is present in 30% of all colorectal carcinomas. In our previous studies we compared the E- Cadherin, β- Catenin, Fibronectin, Ki 67 and Thymidylate Synthase (TS) expression of SRCC, the intestinal type of colorectal carcinoma (ICRC) to try to explain the pathogenesis, the aggressiveness and the low 5 Fluorouracil (5FU) responsiveness of these tumours. We found that all SRCCs had very low levels of all markers and were in the post- mitotic phase of the cell cycle. To understand their high metastatic capability we assessed …
Occupational exposure to endocrine disruptors and lymphoma risk in a multi-centric European study
2015
Background: Incidence rates of lymphoma are usually higher in men than in women, and oestrogens may protect against lymphoma. Methods: We evaluated occupational exposure to endocrine disrupting chemicals (EDCs) among 2457 controls and 2178 incident lymphoma cases and subtypes from the European Epilymph study. Results: Over 30 years of exposure to EDCs compared to no exposure was associated with a 24% increased risk of mature B-cell neoplasms (P-trend=0.02). Associations were observed among men, but not women. Conclusions: Prolonged occupational exposure to endocrine disruptors seems to be moderately associated with some lymphoma subtypes. © 2015 Cancer Research UK. All rights reserved.
Prognostic value of nuclear matrix protein expression in localized prostate cancer.
2012
The aim of the study was to correlate nuclear matrix (NM) protein expression profiles with the risk of PSA progression or death in early prostate cancer (PCa).High-resolution two-dimensional gel electrophoresis (2D-PAGE) was used to identify tumor-associated NM proteins in the PCa specimens obtained from 94 patients. The association between the expression of each protein and the probability of PSA progression or death was studied through univariate analysis. Unsupervised hierarchical clustering analysis was then used to generate patient clusters showing comparable outcomes by including the proteins that were predictive at univariate analysis. PSA-free and overall survival curves relative to…
Quantitative modeling of clinical, cellular, and extracellular matrix variables suggest prognostic indicators in cancer: a model in neuroblastoma
2014
BACKGROUND: Risk classification and treatment stratification for cancer patients is restricted by our incomplete picture of the complex and unknown interactions between the patient's organism and tumor tissues (transformed cells supported by tumor stroma). Moreover, all clinical factors and laboratory studies used to indicate treatment effectiveness and outcomes are by their nature a simplification of the biological system of cancer, and cannot yet incorporate all possible prognostic indicators. METHODS: A multiparametric analysis on 184 tumor cylinders was performed. To highlight the benefit of integrating digitized medical imaging into this field, we present the results of computational s…