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Biobanks are driving motors of precision and personalized medicine by providing high-quality biological material/data through the standardization and harmonization of their collection, preservation, and distribution. UPO Biobank was established in 2020 as an institutional, disease, and population biobank within the University of Piemonte Orientale (UPO) for the promotion and support of high-quality, multidisciplinary studies. UPO Biobank collaborates with UPO researchers, sustaining academic translational research, and supports the Novara Cohort Study, a longitudinal cohort study involving the population in the Novara area that will collect data and biological specimens that will be available for epidemiological, public health, and biological studies on aging. UPO Biobank has been developed by implementing the quality standards for the field and the ethical and legal issues and normative about privacy protection, data collection, and sharing. As a member of the "Biobanking and Biomolecular Resources Research Infrastructure" (BBMRI) network, UPO Biobank aims to expand its activity worldwide and launch cooperation with new national and international partners and researchers. The objective of this manuscript is to report an institutional and operational experience through the description of the technical and procedural solutions and ethical and scientific implications associated with the establishment of this university research biobank.
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Among all cancers, colorectal cancer (CRC) is the 3rd most common and the 2nd leading cause of death worldwide. New therapeutic strategies are required to target cancer stem cells (CSCs), a subset of tumor cells highly resistant to present-day therapy and responsible for tumor relapse. CSCs display dynamic genetic and epigenetic alterations that allow quick adaptations to perturbations. Lysine-specific histone demethylase 1A (KDM1A also known as LSD1), a FAD-dependent H3K4me1/2 and H3K9me1/2 demethylase, was found to be upregulated in several tumors and associated with a poor prognosis due to its ability to maintain CSCs staminal features. Here, we explored the potential role of KDM1A targeting in CRC by characterizing the effect of KDM1A silencing in differentiated and CRC stem cells (CRC-SCs). In CRC samples, KDM1A overexpression was associated with a worse prognosis, confirming its role as an independent negative prognostic factor of CRC. Consistently, biological assays such as methylcellulose colony formation, invasion, and migration assays demonstrated a significantly decreased self-renewal potential, as well as migration and invasion potential upon KDM1A silencing. Our untargeted multi-omics approach (transcriptomic and proteomic) revealed the association of KDM1A silencing with CRC-SCs cytoskeletal and metabolism remodeling towards a differentiated phenotype, supporting the role of KDM1A in CRC cells stemness maintenance. Also, KDM1A silencing resulted in up-regulation of miR-506-3p, previously reported to play a tumor-suppressive role in CRC. Lastly, loss of KDM1A markedly reduced 53BP1 DNA repair foci, implying the involvement of KDM1A in the DNA damage response. Overall, our results indicate that KDM1A impacts CRC progression in several non-overlapping ways, and therefore it represents a promising epigenetic target to prevent tumor relapse.
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Extracellular vesicles (EVs) isolated from plasma are increasingly recognized as promising circulating biomarkers for disease discovery and progression, as well as for therapeutic drug delivery. The scientific community underlined the necessity of standard operative procedures for the isolation and storage of the EVs to ensure robust results. The understanding of the impact of the pre-analytical variables is still limited and some considerations about plasma anticoagulants and isolation methods are necessary. Therefore, we performed a comparison study between EVs isolated by ultracentrifugation and by affinity substrate separation from plasma EDTA and sodium citrate. The EVs were characterized by Nano Tracking Analysis, Western Blot, cytofluorimetric analysis of surface markers, and lipidomic analysis. While anticoagulants did not significantly alter any of the analyzed parameters, the isolation methods influenced EVs size, purity, surface markers expression and lipidomic profile. Compared to ultracentrifugation, affinity substrate separation yielded bigger particles highly enriched in tetraspanins (CD9, CD63, CD81), fatty acids and glycerolipids, with a predominant LDL- and vLDL-like contamination. Herein, we highlighted that the isolation method should be carefully evaluated prior to study design and the need of standardized operative procedures for EVs isolation and application to biomarkers discovery.
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Anticoagulantes , Vesículas Extracelulares , Humanos , Anticoagulantes/farmacología , Anticoagulantes/metabolismo , Vesículas Extracelulares/metabolismo , Plasma/metabolismo , Biomarcadores/metabolismo , Western BlottingRESUMEN
Biobanks have established a critical role in biomedical research by collecting, preserving, organizing, and disseminating biospecimens and related health data, contributing to precision medicine development. Participation in biobanks is influenced by several factors, such as trust in institutions and scientists, knowledge about biobanking, and the consideration of benefit sharing. Understanding public attitudes, fears, and concerns toward biobanking is fundamental to designing targeted interventions to increase trust towards biobanks. The aim of our study was to investigate the level of knowledge and perception of biobanks in students and personnel of the University of Piemonte Orientale. An online questionnaire was designed and administered via e-mail. A total of 17,758 UPO personnel and students were invited to participate in the survey, and 1521 (9.3%) subjects completed the survey. The results showed that 65.0% of the participants were aware of the term "biobank" and knew what the activity of a biobank was, and 76.3% of subjects were willing to provide biospecimens to a research biobank, whereas 67.3% of the respondents were willing to contribute, in addition to biospecimens, their health and lifestyle data. Concerns were raised about the confidentiality of the information (25.6%) and the commercial use of the samples (25.0%). In conclusion, participants were aware of the role that biobanks play in research and were eager to participate for the sake of furthering scientific research. Still, several concerns need to be addressed regarding the confidentiality of the data along with the commercial use of the samples and associated data.
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Bancos de Muestras Biológicas , Investigación Biomédica , Humanos , Universidades , Actitud , Opinión Pública , Encuestas y CuestionariosRESUMEN
Approximately 50% of colorectal cancer (CRC) patients still die from recurrence and metastatic disease, highlighting the need for novel therapeutic strategies. Drug repurposing is attracting increasing attention because, compared to traditional de novo drug discovery processes, it may reduce drug development periods and costs. Epidemiological and preclinical evidence support the antitumor activity of antipsychotic drugs. Herein, we dissect the mechanism of action of the typical antipsychotic spiperone in CRC. Spiperone can reduce the clonogenic potential of stem-like CRC cells (CRC-SCs) and induce cell cycle arrest and apoptosis, in both differentiated and CRC-SCs, at clinically relevant concentrations whose toxicity is negligible for non-neoplastic cells. Analysis of intracellular Ca2+ kinetics upon spiperone treatment revealed a massive phospholipase C (PLC)-dependent endoplasmic reticulum (ER) Ca2+ release, resulting in ER Ca2+ homeostasis disruption. RNA sequencing revealed unfolded protein response (UPR) activation, ER stress, and induction of apoptosis, along with IRE1-dependent decay of mRNA (RIDD) activation. Lipidomic analysis showed a significant alteration of lipid profile and, in particular, of sphingolipids. Damage to the Golgi apparatus was also observed. Our data suggest that spiperone can represent an effective drug in the treatment of CRC, and that ER stress induction, along with lipid metabolism alteration, represents effective druggable pathways in CRC.
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BACKGROUND: Based on the medical history and laboratory analytical tests, a patient presenting symptoms compatible with Chronic Fatigue Syndrome was suspected of metal intoxication; therefore, a chelating therapy was attempted. In parallel, the profile of elemental excretion in urine was determined. METHODS: Chelation therapy by CaNa2EDTA was administered every two weeks and urine samples were routinely collected for 17 months. The samples were mineralized with HNO3 69 % and analyzed by Inductively-Coupled Plasma - Mass Spectrometry. Data were processed by multivariate statistical methods. RESULTS: Most of the toxic elements showed a peak of excretion in 12-24 h after EDTA administration, which returned to basal level by 24-36 h after the treatment. Yet, the excretion of some trace elements persisted in the urine collected 26 h after the treatment. CONCLUSIONS: The analysis of excreted metals following the CaNa2EDTA infusion allowed to monitor dynamically the chelation therapy. The chelation therapy was effective in mobilizing and eliminating the principal heavy metals present from the body. However, since such clearance almost vanished 24 h after the treatment, a protocol with more frequent and low-dose administrations is advisable to improve the metal excretion.
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Análisis de Datos , Ácido Edético/química , Espectrometría de Masas/métodos , Terapia por Quelación , HumanosRESUMEN
Rice cultivation requires a large use of pesticides and nutrients to control weed proliferation and improve production. The water quality of four neighboring rice fields located in the Lomellina area (Italian Padana plain) was monitored in this study along with the cultivation period (before, during, and after the period of planting), for two successive agricultural seasons (2015 and 2016). Two paddy fields were traditionally cultivated with wet-seeding and the other fields with dry-seeding. Eighteen sampling points were considered: eight points for surface water, two points for underground water, and eight points for porous cups with two different depths. In order to evaluate the goodness of the paddy field system to maintain unchanged the quality of the inflow with respect to the outflow water, three of the most used herbicides in Italian rice cultivation (imazamox, oxadiazon, and profoxydim) and other physical-chemical parameters were determined, namely biological oxygen demand after 5 days; chemical oxygen demand; total suspended solids; anionic surfactants; total hardness; total amount of phosphorus, nitrogen, and potassium; and heavy metal concentrations. In general, all the collected data confirmed that paddy fields did not contribute to worsen the environmental pollution. The different flooding techniques adopted in the fields did not highlight significant differences in concentrations of pesticides or metals. The pesticides reached their maximum concentration (of the magnitude order of few ng mL-1) on the day after the administration and on the day after the application in the adjacent field. A slight reduction of total As in grain was obtained adopting a dry period from steam elongation up to booting. From the collected data, it was possible to identify a general water flow direction in the paddy fields from north-west to south-east: this prevailing flow direction was useful to understand not only the diffusion of the pesticides and their degradation products in the fields but also that of the nutrients. Concerning nutrients, it was important not to activate a recirculation of the water in the field during the first 10 days from the administration, in order to avoid loss of nitrogen in the water vents or for percolation. Moreover, the monitoring of potassium concentration allowed to avoid the use of unnecessary potassic fertilization when there was already a high amount of this element in the paddy field derived from irrigation. However, all the investigated water quality parameters were under the limits fixed by the European regulation. In addition, the presence of seven unexpected compounds was identified by the nontarget approach in both campaigns in samples collected in the early summer period. Four of these emerging contaminants were identified as N,N-diethyl-meta-toluamide, tricyclazole, amidosulfuron, and one of the imazamox photodegradation products. Although the obtained low concentrations of oxadiazion, tricyclazole, and arsenic, in particular, justified a preexisting contamination of the water inflow or of the investigated paddy area, the obtained results supported the good quality of the paddy water outflow, confirming the rational use of the water resource and the correct use of agronomic practices.
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Agricultura , Monitoreo del Ambiente , Oryza/crecimiento & desarrollo , Contaminantes Químicos del Agua/análisis , Arsénico , Granjas , Agua Subterránea , Metales Pesados/análisis , Nitrógeno/análisis , Oryza/química , Plaguicidas/análisis , Fósforo/análisis , Agua/química , Calidad del AguaRESUMEN
Arbuscular mycorrhizal fungi (AMF) colonize the roots of most terrestrial plant species, improving plant growth, nutrient uptake and biotic/abiotic stress resistance and tolerance. Similarly, plant growth promoting bacteria (PGPB) enhance plant fitness and production. In this study, three different AMF (Funneliformis mosseae, Septoglomus viscosum, and Rhizophagus irregularis) were used in combination with three different strains of Pseudomonas sp. (19Fv1t, 5Vm1K and Pf4) to inoculate plantlets of Fragaria × ananassa var. Eliana F1. The effects of the different fungus/bacterium combinations were assessed on plant growth parameters, fruit production and quality, including health-promoting compounds. Inoculated and uninoculated plants were maintained in a greenhouse for 4 months and irrigated with a nutrient solution at two different phosphate levels. The number of flowers and fruits were recorded weekly. At harvest, fresh and dry weights of roots and shoots, mycorrhizal colonization and concentration of leaf photosynthetic pigments were measured in each plant. The following fruit parameters were recorded: pH, titratable acids, concentration of organic acids, soluble sugars, ascorbic acids, and anthocyanidins; volatile and elemental composition were also evaluated. Data were statistically analyzed by ANOVA and PCA/PCA-DA. Mycorrhizal colonization was higher in plants inoculated with R. irregularis, followed by F. mosseae and S. viscosum. In general, AMF mostly affected the parameters associated with the vegetative portion of the plant, while PGPB were especially relevant for fruit yield and quality. The plant physiological status was differentially affected by inoculations, resulting in enhanced root and shoot biomass. Inoculation with Pf4 bacterial strain increased flower and fruit production per plant and malic acid content in fruits, while decreased the pH value, regardless of the used fungus. Inoculations affected fruit nutritional quality, increasing sugar and anthocyanin concentrations, and modulated pH, malic acid, volatile compounds and elements. In the present study, we show for the first time that strawberry fruit concentration of some elements and/or volatiles can be affected by the presence of specific beneficial soil microorganisms. In addition, our results indicated that it is possible to select the best plant-microorganism combination for field applications, and improving fruit production and quality, also in terms of health promoting properties.
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The authentication and traceability of hazelnuts is very important for both the consumer and the food industry, to safeguard the protected varieties and the food quality. This study investigates the use of a portable FTIR spectrometer coupled to multivariate statistical analysis for the classification of raw hazelnuts. The method discriminates hazelnuts from different origins/cultivars based on differences of the signal intensities of their IR spectra. The multivariate classification methods, namely principal component analysis (PCA) followed by linear discriminant analysis (LDA) and partial least square discriminant analysis (PLS-DA), with or without variable selection, allowed a very good discrimination among the groups, with PLS-DA coupled to variable selection providing the best results. Due to the fast analysis, high sensitivity, simplicity and no sample preparation, the proposed analytical methodology could be successfully used to verify the cultivar of hazelnuts, and the analysis can be performed quickly and directly on site.
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Corylus/clasificación , Análisis Discriminante , Análisis de los Mínimos Cuadrados , Espectrofotometría InfrarrojaRESUMEN
This article deals with the identification of the photo-degradation products of 4-aminocarminic acid potentially present in commercial beverages. Sixteen beverages of different composition but all containing the E120 dye were previously analysed by ultra-high-performance liquid chromatography (UHPLC) coupled with quadrupole-time of flight mass spectrometry to identify the common degradation products of the E120 dye. Since it is plausible to find unauthorised 4-aminocarminic acid in beverages which report generic E120 dye on the label, retrospective analysis was employed here not only to search for the possible presence of 4-aminocarminic acid but also to investigate the potential formation of photo-degradation products derived from this compound. For this purpose, a statistical approach based on Student's t-test was used to compare the degraded beverages containing 4-aminocarminic acid with all the others. Five degradation products were identified and their structures were elucidated on the basis of the high-accuracy and high-resolution of mass and mass/mass spectra. The toxicity of the degradation products was evaluated through the Ames Salmonella/microsome mutagenicity assay. No evidence of mutagenicity was obtained for the beverages subjected or not to irradiation, whereas a toxic effect of the 4-aminocarminic acid standard solution already at 100.0 µg l(-1) was found. This leads, once again, to the conclusion that the toxicity study must be carried out on the beverages in order to take into account of all the possible masking/protection interactions among the ingredients.
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Bebidas/análisis , Carmín/análisis , Colorantes de Alimentos/análisis , Fotólisis , Cromatografía Líquida de Alta Presión , Pruebas de Mutagenicidad , Espectrometría de Masas en TándemRESUMEN
This paper reports the study of the photodegradation reactions that tricyclazole can naturally undergo, under the action of sunlight, in aqueous solutions of standard tricyclazole and of the commercial BEAM(TM) formulation. The analyses are carried out by ultra-high performance liquid chromatography technique coupled with high-resolution tandem mass spectrometry. Analysis of both tricyclazole and BEAM(TM) water solutions undergone to hydrolysis does not evidence new chromatographic peaks with respect to the not treated solutions. On the contrary, analysis of the same samples subjected to sunlight irradiation shows a decreased intensity of tricyclazole signal and the presence of new chromatographic peaks. Two photodegradation products of tricyclazole have been identified, one of which has been also quantified, being the commercial standard available. The pattern is similar for the solutions of the standard fungicide and of the BEAM(TM) formulation. The results obtained from eco-toxicological tests show that toxicity of tricyclazole standard solutions is greater than that of the irradiated ones, whereas toxicity levels of all the BEAM(TM) solutions investigated (non-irradiated, irradiated, and hydrolyzed) are comparable and lower than those shown by tricyclazole standard solutions. Experiments performed in paddy water solution show that there is no difference in the degradation products formed.
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Fotólisis , Luz Solar , Tiazoles/química , Agua/química , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida , Fungicidas Industriales/química , Hidrólisis , Espectrometría de Masas , Soluciones , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/análisisRESUMEN
The study investigates the sunlight photodegradation process of carminic acid, a natural red colourant used in beverages. For this purpose, both carminic acid aqueous standard solutions and sixteen different commercial beverages, ten containing carminic acid and six containing E120 dye, were subjected to photoirradiation. The results show different patterns of degradation, not only between the standard solutions and the beverages, but also from beverage to beverage. Due to the different beverage recipes, unpredictable reactions take place between the dye and the other ingredients. To identify the dye degradation products in a very complex scenario, a methodology was used, based on the combined use of principal component analysis with discriminant analysis and ultra-high-performance liquid chromatography coupled with tandem high resolution mass spectrometry. The methodology is unaffected by beverage composition and allows the degradation products of carminic acid dye to be identified for each beverage.
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Bebidas/análisis , Carmín/análisis , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Análisis Discriminante , Fotólisis , Análisis de Componente PrincipalRESUMEN
To address the growing interest of consumers for information on the provenance of foodstuffs, the production chain of world renowned Moscato d'Asti white wine has been studied using the distribution of lanthanides as chemical markers. From soil to must, upon every stage of the chain, samples have been taken and analysed with ICP-MS in order to verify whether the original fingerprint of soil is maintained or not along the chain. Results of this traceability study show clearly that lanthanides fingerprint is kept unaltered in the passage soil-grapes-must, while fractionation occurs upon wine clarifying with bentonites. The second part of the work involves a study on 102 samples of Moscato d'Asti musts in order to verify how they reflect the features of the different geographical zones where they come from, and to build a basis to be able to identify possible adulterations performed by addition of foreign musts.
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Oligoelementos/análisis , Vitis/química , Vino/análisis , Geografía , Italia , Elementos de la Serie de los Lantanoides/análisis , Elementos de la Serie de los Lantanoides/metabolismo , Espectrometría de Masas , Control de Calidad , Oligoelementos/metabolismo , Vitis/metabolismoRESUMEN
The use of doping agents, once restricted to professional athletes, has nowadays become a problem of public health, since it also concerns young people and non-competing amateurs in different sports. The use is also diffused in social life for improving physical appearance and enhancing performance and even dietary supplements assumed to improve performance often contain anabolic steroids. While decades ago the so-called "classical doping agents" (like stimulants and narcotics) were used, to-day anabolic steroids are more widely diffused. Anabolic steroids are synthetic substances prepared by introducing modifications in the molecular structure of testosterone, the main natural androgenic anabolic steroid that forms in testes interstitial cells. The first report concerning the use of anabolic steroids by an athlete who searched for increased weight and power dates 1954. In 1974 the misuse of anabolic steroids in sports was banned by the International Olympic Committee and control tests were implemented in 1976 Montreal Olympic Games through radioimmunoassay analysis: the technique, however, only allows for unspecific detection of a limited number of exogenous steroids. Over the years, always new doping substances are synthesized and, as a consequence, the list of prohibited compounds is continuously updated and new suitable analytical methods for their detection and determination in biological matrices are continuously required. In doping control analysis the knowledge of steroid metabolism pathway in human body is of primary importance and the analytical methods must permit the simultaneous detection and determination not only of the forbidden precursor agents but also of their metabolites. In addition, the potential presence and amount in the biological samples of species that can interfere in the analysis should be evaluated. Also the several anabolic steroids, specifically designed to circumvent doping control, put on the market have been incorporated in the list of the prohibited substances of the World Anti-Doping Agency (WADA). In WADA list steroids figure in three main classes, namely anabolic steroids, corticosteroids and substances with anti-estrogenic properties. It must be strongly reminded that assumption of doping agents not only leads to athletes the possible failing of doping tests but causes important health risk and WADA prohibited list establishes criteria to highlight the alteration of the natural steroid profile caused by exogenous administration. Doping control analyses are generally performed in urine, a matrix that provides a prolonged detection time window, and less often in blood, serum, plasma, hair, saliva, and nails. To identify the chemical structures of anabolic steroids the use of mass spectrometry detection is very advantageous. Gas chromatography-mass spectrometry (GC-MS) techniques allowed for the development of comprehensive screening methods. GC-MS methods are sensitive and robust but present the disadvantages of time-consuming sample pretreatment, that is often based on hydrolysis and derivatisation reactions. Liquid chromatography-mass spectrometry (LC-MS) methods have been successfully used to identify and determinate steroids in different matrices, as well as to study their metabolisms. Nowadays, automatic rapid ultra high performance liquid chromatography (UHPLC) tandem mass spectrometry has become the technique of choice for steroid analysis. Due to its generally higher speed, sensitivity, reproducibility and specificity with respect to HPLC, it can be used to simultaneously separate and determinate multi component steroid mixtures. The technique is of huge interest to separate conjugates anabolic androgenic steroids, as it allows efficiency enhancement due to the small particle (sub-2µm) column packing, which provides high peak capacity within analysis times even 5-10 fold shorter than conventional HPLC methods. Modern multiplex instruments can analyze thousands of samples per month so that, notwithstanding the generally high instrumental costs, the cost of the individual assay is affordable. In addition, the improved specificity and resolution offered by time-of-flight or quadrupole time-of-flight mass spectrometry allow their application in doping control analysis or in steroid profiling for accurate and sensitive full mass range acquisition. Aim of the present review is to consider, compare and discuss the applications of the UHPLC/MS methods present in literature for the identification and determination of forbidden steroids and their metabolites in human biological matrices.
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Anabolizantes/análisis , Cromatografía Líquida de Alta Presión/métodos , Doping en los Deportes , Esteroides/análisis , Espectrometría de Masas en Tándem/métodos , HumanosRESUMEN
The study deals with the identification of the degradation products formed by simulated sunlight photoirradiation in a commercial beverage that contains Allura Red AC dye. An UHPLC-MS/MS method, that makes use of hybrid triple quadrupole/linear ion trap, was developed. In the identification step the software tool information dependent acquisition (IDA) was used to automatically obtain information about the species present and to build a multiple reaction monitoring (MRM) method with the MS/MS fragmentation pattern of the species considered. The results indicate that the identified degradation products are formed from side-reactions and/or interactions among the dye and other ingredients present in the beverage (ascorbic acid, citric acid, sucrose, aromas, strawberry juice, and extract of chamomile flowers). The presence of aromatic amine or amide functionalities in the chemical structures proposed for the degradation products might suggest potential hazards to consumer health.
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Compuestos Azo/química , Bebidas/análisis , Cromatografía Líquida de Alta Presión/métodos , Colorantes de Alimentos/química , Espectrometría de Masas en Tándem/métodos , Compuestos Azo/efectos de la radiación , Bebidas/efectos de la radiación , Colorantes de Alimentos/efectos de la radiación , Inocuidad de los Alimentos , FotólisisRESUMEN
The broad group of biogenic amines includes polyamines and catecholamines, whose presence in human tissues and biological fluids can give important diagnostic information and act as marker of many pathologies. In particular, polyamines are involved in cancer cell growth while catecholamines act as neurotransmitters and hormones. Their simultaneous determination in biological tissues and fluids is therefore an important task. A high-performance liquid chromatography tandem mass spectrometry method is presented here for the simultaneous determination in urine of 16 biogenic amines: adrenaline (epinephrine), agmatine, cadaverine, dopamine, histamine, 3-methoxytyramine, noradrenaline (norepinephrine), norephedrine, octopamine, 2-phenylethylamine, putrescine, serotonin, spermidine, spermine, tryptamine, and tyramine. The method does not require any derivatization step. To guarantee the maximum of sensitivity, the mass spectrometer works in selected reaction monitoring mode, monitoring for each analyte the two most intensive transitions. Method validation includes the evaluation of limits of detection (that range from 0.3 to 6.6 µg L(-1)), limits of quantitation (that range from 1.0 to 21.9 µg L(-1)), linearity range (three orders of magnitude), recovery, intra- and inter-day precision on both concentration, and retention time. Recovery (R) is shown not to depend on the analyte concentration: the average R percent ranges from 72.9 to 100.0 %. Particular attention is devoted to the matrix effect and the correlated phenomena of ion enhancement or suppression in mass spectrometry detection.
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Aminas Biogénicas/orina , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Aminas Biogénicas/química , Femenino , Humanos , Masculino , Estructura MolecularRESUMEN
The study deals with the identification of the degradation products formed by simulated sunlight photoirradiation in a beverage that contains Allura Red AC (E129) dye. An UHPLC-MS/MS method that makes use of high resolution quadrupole-time-of-flight mass spectrometer, was developed. For the identification of the degradation products the software tool Information Dependent Acquisition (IDA) was used to automatically obtain information about the high resolution MS and MS/MS spectra of the species present. Accurate mass data were essential for the identification of the appropriate elemental composition: the elucidation of unknown chemical structures was obtained by using powerful software to mine the recorded chromatogram. The identified degradation products are formed from side-reactions and/or from the interactions taking place among the dye and other ingredients present in the beverage (i.e. ascorbic acid, citric acid, sucrose, aromas, strawberry juice and extract of chamomile flowers). The presence of aromatic amine or amide groups in the chemical structures of the degradation products suggests the potential hazard for the consumer health.
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A new approach for monitoring the state of conservation of cultural heritage objects surfaces is being developed. The technique utilizes multi-spectral imaging, multivariate analysis and statistical process control theory for the automatic detection of a possible deterioration process, its localization and identification, and the wavelengths most sensitive to detecting this before the human eye can detect the damage or potential degradation changes occur. A series of virtual degradation analyses were performed on images of parchment in order to test the proposed algorithm in controlled conditions. The spectral image of a Dead Sea Scroll (DSS) parchment, IAA (Israel Antiquities Authority) inventory plate # 279, 4Q501 Apocryphal Lamentations B, taken during the 2008 Pilot of the DSS Digitization Project, was chosen for the simulation.
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The aim of this project is the development of a noninvasive technique based on LED multispectral imaging (MSI) for monitoring the conservation state of the Dead Sea Scrolls (DSS) collection. It is well-known that changes in the parchment reflectance drive the transition of the scrolls from legible to illegible. Capitalizing on this fact, we will use spectral imaging to detect changes in the reflectance before they become visible to the human eye. The technique uses multivariate analysis and statistical process control theory. The present study was carried out on a "sample" parchment of calfskin. The monitoring of the surface of a commercial modern parchment aged consecutively for 2 h and 6 h at 80 °C and 50% relative humidity (ASTM) was performed at the Imaging Lab of the Library of Congress (Washington, DC, U.S.A.). MSI is here carried out in the vis-NIR range limited to 1 µm, with a number of bands of 13 and bandwidths that range from about 10 nm in UV to 40 nm in IR. Results showed that we could detect and locate changing pixels, on the basis of reflectance changes, after only a few "hours" of aging.
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An on-line solid phase extraction (SPE) ultra high performance liquid chromatography tandem mass spectrometry method has been developed for the simultaneous identification and determination of thirteen polycyclic aromatic hydrocarbons (PAHs) and twelve aldehydes (derivatized with 2,4-dinitrophenylhydrazine). The chromatographic conditions have been optimized to obtain the maximum of sensitivity and resolution taking into account the different retention interactions and the different ionization conditions of PAHs and derivatized aldehydes. LOD values ranging from 0.028 to 0.768 µg L(-1) for PAHs and from 0.002 to 0.125 µg L(-1) for aldehydes were obtained. The resolution permitted the separation of four couples of PAH isomers. Sample pre-treatment and SPE were optimized in order to apply the whole methodology to the analysis of different food matrices as salmon, frankfurter, steak, and pork chop, subjected to different cooking modes (smoked, grilled, cooked in oil or in butter). Particular attention was devoted to the evaluation of matrix effect that was significantly reduced through the on-line SPE treatment. For each food matrix the method detection limits, the method quantitation limits, and the recovery R were evaluated. R was shown not to depend on analyte concentration in the explored concentration range (LOQ - 50.000 µg L(-1)): the average R percent ranges from 70.6% to 120.0%.