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Valencia, Spain

Kuligowski J.,Health Research Institute La Fe | Perez-Guaita D.,University of Valencia | Escobar J.,Health Research Institute La Fe | Lliso I.,Health Research Institute La Fe | And 5 more authors.

Liquid chromatography-mass spectrometry (LC-MS) has been increasingly used in biomedicine to study the dynamic metabolomic responses of biological systems under different physiological or pathological conditions. To obtain an integrated snapshot of the system, metabolomic methods in biomedicine typically analyze biofluids (e.g. plasma) that require clean-up before being injected into LC-MS systems. However, high resolution LC-MS is costly in terms of resources required for sample and data analysis and care must be taken to prevent chemical (e.g. ion suppression) or statistical artifacts. Because of that, the effect of sample preparation on the metabolomic profile during metabolomic method development is often overlooked. This work combines an Attenuated Total Reflectance-Fourier transform infrared (ATR-FTIR) and a multivariate exploratory data analysis for a cost-effective qualitative evaluation of major changes in sample composition during sample preparation. ATR-FTIR and LC-time of flight mass spectrometry (TOFMS) data from the analysis of a set of plasma samples precipitated using acetonitrile, methanol and acetone performed in parallel were used as a model example. Biochemical information obtained from the analysis of the ATR-FTIR and LC-TOFMS data was thoroughly compared to evaluate the strengths and shortcomings of FTIR biospectroscopy for assessing sample preparation in metabolomics studies. Results obtained show the feasibility of ATR-FTIR for the evaluation of major trends in the plasma composition changes among different sample pretreatments, providing information in terms of e.g., amino acids, proteins, lipids and carbohydrates overall contents comparable to those found by LC-TOFMS. © 2014 Elsevier B.V. Source

Kuligowski J.,University of Valencia | Quintas G.,Leitat Technological Center | Herwig C.,Vienna University of Technology | Lendl B.,Vienna University of Technology

This paper shows the ease of application and usefulness of mid-IR measurements for the investigation of orthogonal cell states on the example of the analysis of Pichia pastoris cells. A rapid method for the discrimination of entire yeast cells grown under carbon and nitrogen-limited conditions based on the direct acquisition of mid-IR spectra and partial least squares discriminant analysis (PLS-DA) is described. The obtained PLS-DA model was extensively validated employing two different validation strategies: (i) statistical validation employing a method based on permutation testing and (ii) external validation splitting the available data into two independent sub-sets. The Variable Importance in Projection scores of the PLS-DA model provided deeper insight into the differences between the two investigated states. Hence, we demonstrate the feasibility of a method which uses IR spectra from intact cells that may be employed in a second step as an in-line tool in process development and process control along Quality by Design principles. © 2012 Elsevier B.V. Source

Salvans S.,Section of Colon and Rectal Surgery | Salvans S.,Colorectal Cancer Research Group | Mayol X.,Colorectal Cancer Research Group | Alonso S.,Section of Colon and Rectal Surgery | And 9 more authors.
Annals of Surgery

Objective: The aim of this study was to investigate the effect of postoperative peritoneal infection on proliferation, migration, and invasion capacities of cancer cells lines in vitro after surgery for colorectal cancer. Background: Anastomotic leakage is associated with higher rates of recurrence after surgery for colorectal cancer. However, the mechanisms responsible are unknown. We hypothesized that the infection-induced inflammatory response may enhance tumor progression features of residual cancer cells. Methods: Prospective matched cohort study. Patients undergoing surgery for colorectal cancer with curative intent (January 2008-March 2012) were included. Patients who had an anastomotic leak or intra-abdominal abscess were included in the infection group (n = 47). For each case patient, another patient with an uncomplicated postoperative course was selected for the control group (n = 47). In vitro treatments on cancer cell lines (MDA-MB-231 and SW620) were performed using baseline and postoperative serumand peritoneal fluid samples to determine cell proliferation and cell migration/invasion activities. Results: Postoperative peritoneal fluid from infected patients enhanced both cell migration (infection: 140 ± 85 vs control: 94 ± 30; P = 0.016) and cell invasion (infection: 117 ± 31 vs control: 103 ± 16; P = 0.024) capacities of cancer cell lines.With serum samples, these effects were only observed in cell migration assays (infection: 98 ± 28 vs control: 87 ± 17; P = 0.005). Some minor activation of cell proliferation was observed by treatment with serum from infection group. Two-year cumulative disease-free survival was significantly lower in patients with postoperative peritoneal infection (infection: 77.6% vs control: 90.6%; P = 0.032). Conclusions: Our results suggest that postoperative peritoneal infection enhances the invasive capacity of residual tumor cells after surgery, thus facilitating their growth to recurrent tumors. Copyright © 2014 by Lippincott Williams & Wilkins. Source

Kuligowski J.,University of Valencia | Quintas G.,Leitat Technological Center | Tauler R.,CSIC - Institute of Chemical and Environmental Research | Lendl B.,Vienna University of Technology | De La Guardia M.,University of Valencia
Analytical Chemistry

The use of multivariate curve resolution-alternating least-squares (MCR-ALS) in liquid chromatography-infrared detection (LC-IR) is troublesome due to the intense background absorption changes during gradient elution. Its use has been facilitated by previous removal of a significant part of the solvent background IR contributions due to common mobile phase systems employed during reversed phase gradient applications. Two straightforward background correction approaches based on simple-to-use interactive self-modeling mixture analysis (SIMPLISMA) and principal component analysis (PCA) are proposed and evaluated on reversed phase gradient LC-IR data sets obtained during the analysis of carbohydrate and nitrophenol mixtures. After subtraction of the calculated background signal, MCR-ALS provided improved signal-to-noise ratios, removed remaining mobile phase and background signal contributions, and resolved overlapping chromatographic peaks. The present approach tends to enable easy-to-use background correction to facilitate the use of MCR-ALS in online LC-IR, even in challenging situations when gradient conditions are employed and only poor chromatographic resolution is achieved. It, therefore, shows great potential to facilitate the full exploitation of the advantages of simultaneous quantification and identification of a vast amount of analytes employing online IR detection, making new exciting applications more accessible. © 2011 American Chemical Society. Source

Yada R.Y.,University of Guelph | Buck N.,on behalf of the ILSI Europe Novel Foods and Nanotechnology Task Force | Canady R.,Intl Life Science Institute Research Foundation | Demerlis C.,Colorcon Ltd | And 13 more authors.
Comprehensive Reviews in Food Science and Food Safety

The NanoRelease Food Additive project developed a catalog to identify potential engineered nanomaterials (ENMs) used as ingredients, using various food-related databases. To avoid ongoing debate on defining the term nanomaterial, NanoRelease did not use any specific definition other than the ingredient is not naturally part of the food chain, and its dimensions are measured in the nanoscale. Potential nanomaterials were categorized based on physical similarity; analysis indicated that the range of ENMs declared as being in the food chain was limited. Much of the catalog's information was obtained from product labeling, likely resulting in both underreporting (inconsistent or absent requirements for labeling) and/or overreporting (inability to validate entries, or the term nano was used, although no ENM material was present). Three categories of ingredients were identified: emulsions, dispersions, and their water-soluble powdered preparations (including lipid-based structures); solid encapsulates (solid structures containing an active material); and metallic or other inorganic particles. Although much is known regarding the physical/chemical properties for these ingredient categories, it is critical to understand whether these properties undergo changes following their interaction with food matrices during preparation and storage. It is also important to determine whether free ENMs are likely to be present within the gastrointestinal tract and whether uptake of ENMs may occur in their nanoform physical state. A practical decision-making scheme was developed to help manage testing requirements. © 2014 Institute of Food Technologists®. Source

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