ABSTRACT
Six-axis force/torque sensors are increasingly needed in mechanical engineering. Here, we introduce a flexure-based design for such sensors, which solves some of the drawbacks of the existing designs. In particular, it is backlash-free, it can be wirelessly monitored, it exactly enforces 90° angles between axes, and it enables visual inspection of the monitored system, thanks to its hollow structure. We first describe the generic design, implementation, and calibration procedure. We then demonstrate its capabilities through three illustration examples relevant to the field of tribology: low friction measurements under ultra-high vacuum, multi-directional friction measurements of elastomer contacts, and force/torque-based contact position monitoring.
ABSTRACT
BACKGROUND: Second primary cancers (SPCs) are diagnosed in over 5% of patients after a first primary cancer (FPC). We explore here the impact of immune checkpoint inhibitors (ICIs) given for an FPC on the risk of SPC in different age groups, cancer types and treatments. PATIENTS AND METHODS: The files of the 46 829 patients diagnosed with an FPC in the Centre Léon Bérard from 2013 to 2018 were analyzed. Structured data were extracted and electronic patient records were screened using a natural language processing tool, with validation using manual screening of 2818 files of patients. Univariate and multivariate analyses of the incidence of SPC according to patient characteristics and treatment were conducted. RESULTS: Among the 46 829 patients, 1830 (3.9%) had a diagnosis of SPC with a median interval of 11.1 months (range 0-78 months); 18 128 (38.7%) received cytotoxic chemotherapy (CC) and 1163 (2.5%) received ICIs for the treatment of the FPC in this period. SPCs were observed in 7/1163 (0.6%) patients who had received ICIs for their FPC versus 437/16 997 (2.6%) patients receiving CC and no ICIs for the FPC versus 1386/28 669 (4.8%) for patients receiving neither CC nor ICIs for the FPC. This reduction was observed at all ages and for all histotypes analyzed. Treatment with ICIs and/or CC for the FPC are associated with a reduced risk of SPC in multivariate analysis. CONCLUSION: Immunotherapy with ICIs alone and in combination with CC was found to be associated with a reduced incidence of SPC for all ages and cancer types.
Subject(s)
Immune Checkpoint Inhibitors , Neoplasms, Second Primary , Humans , Incidence , Neoplasms, Second Primary/epidemiologyABSTRACT
BACKGROUND: An array of bioactive compounds with health-promoting effects has been described in several species of macroalgae. Among them, phytoprostanes (PhytoPs) and phytofurans (PhytoFs), both autoxidation products of α-linolenic acid, have been seen to exert immunomodulatory and antiinflammatory activities in vitro. The purpose of this study was to explore the bioaccesibility, bioavailability, and bioactivity of PhytoPs and PhytoFs obtained from the edible red algae Gracilaria longissima, and to gain insight into the anti-inflammatory activity of their bioavailable fraction in human endothelial cells. METHODS: The PhytoPs and PhytoFs profile and concentration of G. longissima were determined by UHPLC-QqQ-MS/MS. Algal samples were processed following a standardised digestion method including gastric, intestinal, and gastrointestinal digestion. The bioavailability of the PhytoPs and PhytoFs in the characterized fractions was assessed in a Caco-2 cell monolayer model of the intestinal barrier. The inflammation response of these prostaglandin-like compounds in human endothelial cells, after intestinal absorption, was investigated in vitro. RESULTS: Simulated digestions significantly reduced the concentration of PhytoPs and PhytoFs up to 1.17 and 0.42 µg per 100 g, respectively, on average, although permeability through the Caco-2 cell monolayer was high (up to 88.2 and 97.7%, on average, respectively). PhytoP and PhytoF-enriched extracts of raw algae impaired the expression of ICAM-1 and IL-6 inflammation markers. The inflammation markers progressed in contrast to the relative concentrations of bioactive oxylipins, suggesting pro- or anti-inflammatory activity on their part. In this aspect, the cross-reactivity of these compounds with diverse receptors, and their relative concentration could explain the diversity of the effects found in the current study. CONCLUSIONS: The results indicate that PhytoPs and PhytoFs display complex pharmacological profiles probably mediated through their different actions and affinities in the endothelium.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Endothelial Cells/drug effects , Furans/pharmacology , Gracilaria/chemistry , Oxylipins/pharmacology , Phytochemicals/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Anti-Inflammatory Agents, Non-Steroidal/toxicity , Biological Availability , Caco-2 Cells , Digestion , Endothelial Cells/metabolism , Fatty Acids, Unsaturated/pharmacokinetics , Fatty Acids, Unsaturated/pharmacology , Fatty Acids, Unsaturated/toxicity , Furans/pharmacokinetics , Furans/toxicity , Humans , In Vitro Techniques , Intercellular Adhesion Molecule-1/metabolism , Interleukin-6/metabolism , Intestinal Mucosa/drug effects , Intestinal Mucosa/metabolism , Oxylipins/pharmacokinetics , Oxylipins/toxicity , Phytochemicals/pharmacokinetics , Phytochemicals/toxicity , Structure-Activity RelationshipABSTRACT
Given the growing interest in phytoprostanes (PhytoPs) and phytofurans (PhytoFs) in the fields of plant physiology, biotechnology, and biological function, the present study aims to optimize a method of enzymatic hydrolysis that utilizes bacterial and yeast esterases that allow the appropriate quantification of PhytoPs and PhytoFs. To obtain the highest concentration of PhytoPs and PhytoFs, a response surface methodology/Box-Behnken design was used to optimize the hydrolysis conditions. Based on the information available in the literature on the most critical parameters that influence the activity of esterases, the three variables selected for the study were temperature (°C), time (min), and enzyme concentration (%). The optimal hydrolysis conditions retrieved differed between PhytoPs (21.5 °C, 5.7 min, and 0.61 µg of enzyme per reaction) and PhytoFs (20.0 °C, 5.0 min, and 2.17 µg of enzyme per reaction) and provided up to 25.1- and 1.7-fold higher contents relative to nonhydrolyzed extracts. The models were validated by comparing theoretical and experimental values for PhytoP and PhytoF yields (1.01 and 1.06 theoretical/experimental rates, respectively). The optimal conditions were evaluated for their relative influence on the yield of individual nonesterified PhytoPs and PhytoFs to define the limitations of the models for obtaining the highest concentration of most considered compounds. In conclusion, the models developed provided valuable alternatives to the currently applied methods using unspecific alkaline hydrolysis to obtain free nonesterified PhytoPs and PhytoFs, which give rise to more specific hydrolysis of PhytoP and PhytoF esters, reducing the degradation of free compounds by classical chemical procedures.
Subject(s)
Furans , Pisum sativum , Esterases , Hydrolysis , Plant ExtractsABSTRACT
We assessed the performance of the VITEK® MS IVD V3.0 matrix-assisted laser desorption ionization - time of flight mass spectrometry (MALDI-ToF MS) V3.0 database for the identification of Nocardia spp. as compared with targeted DNA sequencing. A collection of 222 DNA sequence-defined Nocardia spp. strains encompassing 18 different species present or not in the database was tested. Bromocresol purple agar (BCP) and Columbia agar +5% sheep's blood (COS) culture media were used together with two different preparation steps: direct smear and a "3 attempts" procedure that covered (1) spotting of an extract, (2) new spotting of the same extract, and (3) spotting of a new extract. The direct smear protocol yielded low correct identification rates (≤ 15% for both media) whereas protein extraction yielded correct identification results (> 67% regardless of the media used.). The use of 2 additional attempts using repeat or new extracts increased correct identification rates to 87% and 91% for BCP and COS, respectively. When using the 3 attempts procedure, the best identification results, independent of media types, were obtained for N. farcinica and N. cyriacigeorgica (100%). Identification attempts 2 and 3 allowed to increase the number of correct identifications (BCP, +20%; COS, +13%). The enhancement in performance during attempts 2 and 3 was remarkable for N. abscessus (81% for both media) and low prevalence species (BCP, 70%; COS, 85%). Up to 3.4% and 2.4% of the strains belonging to species present in the database were misidentified with BCP and COS media, respectively. In 1.9% of the cases for BCP and 1.4% for COS, these misidentifications concerned a species belonging to the same phylogenetic complex. Concerning strains that are not claimed in the V3.0 database, N. puris and N. goodfellowi generated "No identification" results and 100% of the strains belonging to N. arthritidis, N.cerradoensis, and N. altamirensis yielded a misidentification within the same phylogenetic complex. Vitek® MS IVD V3.0 is an accurate and useful tool for identification of Nocardia spp.
Subject(s)
Bacteriological Techniques , Databases, Factual , Nocardia Infections/diagnosis , Nocardia Infections/microbiology , Nocardia/classification , Algorithms , Bacterial Proteins/isolation & purification , Humans , Nocardia/metabolism , Reagent Kits, Diagnostic , Reproducibility of Results , WorkflowABSTRACT
In rice crops, fertilization is a naturalized practice, although inefficient, that could be improved by applying foliar fertilization. Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) are products of α-linolenic acid peroxidation, useful as biomarkers of oxidative degradation in higher plants. The objective was to determine the effect of the foliar fertilization on the concentration of PhytoPs and PhytoFs and its relationships with modifications of yield and quality of rice productions. It was described that the concentration of biomarkers of stress decreased with the application of foliar fertilization, being the response significantly different depending the genotypes and compound monitored. Moreover, fertilization did not modify significantly the parameters of yield (961.2 g m-2), 1000 whole-grain (21.2 g), and protein content (10.7% dry matter). Therefore, this is the first work that describes the effect of fertilization on PhytoPs and PhytoFs in rice genotypes and reinforces the capacity of these compounds as biomarkers to monitor specific abiotic stress, in this case, represented by nutritional stress.
Subject(s)
Fertilizers/analysis , Oryza/metabolism , Oxidative Stress , Biomarkers/analysis , Biomarkers/metabolism , Furans/analysis , Furans/metabolism , Oryza/chemistry , Oryza/growth & development , Plant Leaves/chemistry , Plant Leaves/growth & development , Plant Leaves/metabolism , Plant Proteins/genetics , Plant Proteins/metabolismABSTRACT
Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) are oxylipins synthesized by nonenzymatic peroxidation of α-linolenic acid. These compounds are biomarkers of oxidative degradation in plant foods. In this research, the effect of environment and supplementation with salicylic acid (SA) on PhytoPs and PhytoFs was monitored by ultra-high-performance liquid chromatography coupled to electrospray ionization and triple quadrupole mass spectrometry (UHPLC-ESI-QqQ-MS/MS) on seven rice genotypes from Oryza sativa L. subsp. japonica. The plastic cover environment and spray application with 1 and 15 mM SA produced a reduction in the concentration of most of these newly established stress biomarkers [9-F1t-PhytoP, ent-16-F1t-PhytoP, ent-16- epi-16-F1t-PhytoP, 9-D1t-PhytoP, 9- epi-9-D1t-PhytoP, 16-B1-PhytoP, 9-L1-PhytoP, ent-16( RS)-9- epi-ST-Δ14-10-PhytoF, ent-9( RS)-12- epi-ST-Δ10-13-PhytoF, and ent-16( RS)-13- epi-ST-Δ14-9-PhytoF] by 60.7% on average. The modification observed in the level of PhytoPs and PhytoFs differed according to the specific oxylipins and genotype, demonstrating a close linkage between genetic features and resistance to abiotic stress, to some extent mediated by the sensitivity of plants to the plant hormone SA that participates in the physiological response of higher plants to stress. Thus, in plants exposed to stressing factors, SA contribute to modulating the redox balance, minimizing the oxidation of fatty acids and thus the syntheis of oxylipins. These results indicated that SA could be a promising tool for managing the thermotolerance of rice crop. However, it remains necessary to study the mechanism of action of PhytoPs and PhytoFs in biochemical processes related to the defense of plants and define their role as stress biomarkers through a nonenzymatic pathway.
Subject(s)
Oryza/drug effects , Oryza/growth & development , Oxylipins/metabolism , Plant Growth Regulators/pharmacology , Salicylic Acid/pharmacology , Biomarkers/chemistry , Biomarkers/metabolism , Chromatography, High Pressure Liquid , Environment , Oryza/chemistry , Oryza/metabolism , Oxylipins/chemistry , Plant Growth Regulators/analysis , Salicylic Acid/analysis , Tandem Mass SpectrometryABSTRACT
F2-isoprostanes (F2-IsoP) are formed in vivo via free radical peroxidation of arachidonic acid. Enhanced oxidative stress is implicated in the development of atherosclerosis in humans and F2-IsoP have been detected in atherosclerotic plaque. Colony stimulating factor-1 (CSF-1) is essential to macrophage survival, proliferation and differentiation and has been detected in human atherosclerotic plaques. Accumulation of macrophages within the vascular wall is an important component of atherosclerosis but little is known about the effect of F2-IsoP on the migration of these cells. Our aim was to examine the effect of free and lipid-bound 15-F2t-isoprostane (15-F2t-IsoP) on macrophage migration and investigate the signalling pathways involved. Mouse macrophages (cell line BAC1.2F5) were pre-incubated with 15-F2t-IsoP (free, bound to cholesterol or monoacylglycerol or within oxidized phospholipid) and cell migration was assessed using chemotaxis towards CSF-1 in Boyden chambers. Migration was also measured using the wound healing assay with primary mouse bone marrow derived macrophages. We showed that 15-F2t-IsoP dose-dependently inhibited BAC1.2F5 macrophage spreading and adhesion but stimulated their migration towards CSF-1, with maximum effect at 10⯵M. Analysis of CSF-1 stimulated signalling pathways in BAC1.2F5 macrophages showed that phosphorylation of Akt, a key mediator of cell migration, and one of its regulators, the mTORC2 component, Rictor, was significantly decreased. In contrast, phosphorylation of the adhesion kinases, FAK and Pyk2, and the adhesion scaffold protein, paxillin, was enhanced after treatment with 15-F2t-IsoP. Mouse bone marrow macrophages were transfected with FAK or Pyk2 small interfering RNA (siRNA) to examine the role of FAK and Pyk2 in 15-F2t-IsoP signalling. Pyk2 silencing inhibited 15-F2t-IsoP-induced reduction in cell area and phospho-paxillin adhesion numbers. The size distribution of adhesions in the presence of 15-F2t-IsoP was also affected by Pyk2 silencing and there was a trend for Pyk2 silencing to reduce 15-F2t-IsoP-stimulated macrophage migration. These results demonstrate that 15-F2t-IsoP affects macrophage adhesions and migration, which are integral components of macrophage involvement in atherosclerosis.
Subject(s)
Atherosclerosis/genetics , F2-Isoprostanes/metabolism , Macrophage Colony-Stimulating Factor/genetics , Plaque, Atherosclerotic/genetics , Animals , Atherosclerosis/metabolism , Atherosclerosis/pathology , Cell Adhesion/genetics , Cell Differentiation/genetics , Cell Movement/genetics , Cell Proliferation/genetics , F2-Isoprostanes/genetics , Free Radicals/metabolism , Humans , Macrophage Colony-Stimulating Factor/metabolism , Macrophages/metabolism , Mice , Oxidative Stress/genetics , Phosphorylation/genetics , Plaque, Atherosclerotic/metabolism , Plaque, Atherosclerotic/pathology , Proto-Oncogene Proteins c-akt/genetics , Rapamycin-Insensitive Companion of mTOR Protein/geneticsABSTRACT
This study aims at genetic characterization and phylogenetic relationships of Nocardia brasiliensis focusing by using housekeeping rrs, hsp65, and sodA genes. N. brasiliensis is the species responsible for 80% of cases of actinomycetoma, one form of cutaneous nocardiosis which occurs mainly in tropical regions reaching immunocompetent patients in which the disease can lead to amputation. We analyze 36 indigenous cases of N. brasiliensis that happened in France. Phylogenetic analysis targeting rrs gene showed no robustness at phylogenetic nodes level. However, the use of a concatenation of hsp65 and sodA genes showed that the tested strains surprisingly ranked in 3 well-defined genotypes. Genotypes 2 and 3 were phylogenetically closer to each other and both diverged from genotype 1 sustained by a high bootstrap of 81%. This last genotype hosts all the cases of pulmonary forms (3), the sole cerebral form, and almost all the cases of immunocompromised patients (3 out of 4). Moreover, excepting one of them, all the strains belonging to this group present a susceptibility to imipenem which is not the case in the other genotypes that rarely count among them strains being susceptible to this drug. The haplotype diversity (Hd) of hsp65 (0.927) and sodA (0.885) genes was higher than that of rrs (0.824). For this gene, we obtained 16 polymorphic sites whereas, for hsp65 and sodA genes, up to 27 and 29 were identified, respectively. This study reveals that these two genes have an important genetic discriminatory power for the evaluation of the intraspecies genetic variability of N. brasiliensis and they may be useful for identification purposes at species level. This study also reveals the possible existence of a new species harbored by genotype 1.
Subject(s)
Bacterial Proteins/genetics , Genetic Variation , Nocardia Infections/genetics , Superoxide Dismutase-1/genetics , France/epidemiology , Humans , Nocardia/genetics , Nocardia/pathogenicity , Nocardia Infections/epidemiology , Nocardia Infections/microbiology , Nocardia Infections/pathology , PhylogenyABSTRACT
Nocardial brain abscess is often occurring in immunocompromised patients. It is uncommon in immunocompetent individuals. Here, the authors describe a case of cerebral and pulmonary nocardiosis mimicking a metastatic tumor in an apparently health 40-year-old Algerian male. The patient presented multiple brain abscess revealed by inaugural epileptic seizure. He was afebrile and presented with left hemiparesis. Staging imaging showed a nodular lung lesion in the apical segment of the right lower lobe. The patient underwent double craniotomy for resection of the lesion. Culture of the resected specimen isolated Nocardia abscessus. The patient was initially started on intravenous trimethoprim-sulfamethoxazole and intravenous amikacine. He was switched to oral trimethoprim-sulfamethoxazole. He finished seven months of antibiotic therapy with a good clinical response. Imaging revealed reduction in the brain abscess and a complete resolution of the lung lesion. Cotrimoxazole was stopped after twelve months of therapy. After two years, the health status of our patient improves day after day. He is however regularly under medical supervision for control exams.
Subject(s)
Brain Abscess/diagnosis , Lung Diseases, Fungal/diagnosis , Nocardia Infections/diagnosis , Nocardia/isolation & purification , Adult , Algeria , Brain Abscess/microbiology , Humans , Immunocompetence , Lung Diseases, Fungal/immunology , Male , Nocardia Infections/immunologyABSTRACT
BACKGROUND: Growing evidence indicates a wide array of cellular remodeling in the mucosal microenvironment during irritable bowel syndrome (IBS), which possibly contributes to pathophysiology and symptom generation. Here, we investigated whether enteric glial cells (EGC) may be altered, and which factors/mechanisms lead to these changes. METHODS: Colonic mucosal biopsies of IBS patients (13 IBS-Constipation [IBS-C]; 10 IBS-Diarrhea [IBS-D]; 11 IBS-Mixed [IBS-M]) and 24 healthy controls (HC) were analyzed. Expression of S100ß and GFAP was measured. Cultured rat EGC were incubated with supernatants from mucosal biopsies, then proliferation and Ca2+ response to ATP were analyzed using flow cytometry and Ca2+ imaging. Histamine and histamine 1-receptor (H1R) involvement in the effects of supernatant upon EGC was analyzed. KEY RESULTS: Compared to HC, the mucosal area immunoreactive for S100ß was significantly reduced in biopsies of IBS patients, independently of the IBS subtype. IBS-C supernatants reduced EGC proliferation and IBS-D and IBS-M supernatants reduced Ca2+ response to ATP in EGC. EGC expressed H1R and the effects of supernatant upon Ca2+ response to ATP in EGC were blocked by pyrilamine and reproduced by histamine via H1R. IBS supernatants reduced mRNA expression of connexin-43. The S100ß-stained area was negatively correlated with the frequency and intensity of pain and bloating. CONCLUSION AND INFERENCES: Changes in EGC occur in IBS, involving mucosal soluble factors. Histamine, via activation of H1R-dependent pathways, partly mediates altered Ca2+ response to ATP in EGC. These changes may contribute to the pathophysiology and the perception of pain and bloating in patients with IBS.
Subject(s)
Colon/metabolism , Enteric Nervous System/metabolism , Irritable Bowel Syndrome/metabolism , Neuroglia/metabolism , Adenosine Triphosphate/administration & dosage , Adult , Animals , Calcium/metabolism , Cells, Cultured , Colon/innervation , Female , Humans , Intestinal Mucosa/metabolism , Male , Middle Aged , Neuroglia/drug effects , Rats , S100 Calcium Binding Protein beta Subunit/metabolismABSTRACT
Phytoprostanes and phytofurans (PhytoPs and PhytoFs, respectively) are nonenzymatic lipid peroxidation products derived from α-linolenic acid (C18:3 n-3), considered biomarkers of oxidative degradation in plant foods. The present work profiled these compounds in white and brown grain flours and rice bran from 14 rice cultivars of the subspecies indica and japonica by ultrahigh performance liquid chromatography coupled to electrospray ionization and triple quadrupole mass spectrometry. For PhytoPs, the average concentrations were higher in rice bran (0.01-9.35 ng g-1) than in white and brown grain flours (0.01-1.17 ng g-1). In addition, the evaluation of rice flours for the occurrence PhytoFs evidenced average values 1.77, 4.22, and 10.30 ng g-1 dw in rice bran, brown grain flour, and white grain flour, respectively. A significant correlation was observed between total and individual compounds. The concentrations retrieved suggest rice bran as a valuable source of PhytoPs and PhytoFs that should be considered in further studies on bioavailability and bioactivity of such compounds.
Subject(s)
Flour/analysis , Furans/analysis , Oryza/chemistry , Plant Extracts/analysis , Oryza/classificationABSTRACT
BACKGROUND: Intestinal epithelial barrier (IEB) dysfunction plays a critical role in various intestinal disorders affecting infants and children, including the development of food allergies and colitis. Recent studies highlighted the role of probiotics in regulating IEB functions and behavior in adults, but their effects in the newborn remain largely unknown. We therefore characterized in rat pups, the impact of Lactobacillus fermentum CECT 5716 (L. fermentum) on stress-induced IEB dysfunction, systemic immune response and exploratory behavior. METHODS: Newborn rats received daily by gavage either L. fermentum or water. Intestinal permeability to fluorescein sulfonic acid (FSA) and horseradish peroxidase (HRP) was measured following maternal separation (MS) and water avoidance stress (WAS). Immunohistochemical, transcriptomic, and Western blot analysis of zonula occludens-1 (ZO-1) distribution and expression were performed. Anxiety-like and exploratory behavior was assessed using the elevated plus maze test. Cytokine secretion of activated splenocytes was also evaluated. KEY RESULTS: L. fermentum prevented MS and WAS-induced IEB dysfunction in vivo. L. fermentum reduced permeability to both FSA and HRP in the small intestine but not in the colon. L. fermentum increased expression of ZO-1 and prevented WAS-induced ZO-1 disorganization in ileal epithelial cells. L. fermentum also significantly reduced stress-induced increase in plasma corticosteronemia. In activated splenocytes, L. fermentum enhanced IFNγ secretion while it prevented IL-4 secretion. Finally, L. fermentum increased exploratory behavior. CONCLUSIONS & INFERENCES: These results suggest that L. fermentum could provide a novel tool for the prevention and/or treatment of gastrointestinal disorders associated with altered IEB functions in the newborn.
Subject(s)
Gastrointestinal Diseases/metabolism , Intestinal Mucosa/metabolism , Limosilactobacillus fermentum , Probiotics/administration & dosage , Stress, Psychological/complications , Animals , Animals, Newborn , Colon/metabolism , Epithelial Cells/metabolism , Exploratory Behavior , Female , Gastrointestinal Diseases/complications , Gastrointestinal Diseases/immunology , Gastrointestinal Diseases/therapy , Maternal Deprivation , Permeability , Rats, Sprague-Dawley , Zonula Occludens-1 Protein/metabolismABSTRACT
Phytofurans are novel metabolites produced by non-enzymatic peroxidation of α-linolenic acid. An unprecedented Payne rearrangement-cyclization of a C2-symmetric bis-epoxide permitted construction of the core 3-hydroxy-2,5-disubstituted tetrahydrofuran. LC-MS/MS investigation provided evidence for the presence of phytofurans in nuts and seeds for the first time.
Subject(s)
Furans/chemistry , Nuts/chemistry , Seeds/chemistry , alpha-Linolenic Acid/chemistry , Chromatography, Liquid , Flax , Juglans , Oxidation-Reduction , Pinus , Salvia , Tandem Mass SpectrometryABSTRACT
Isoprostanoids are a group of non-enzymatic oxidized lipids from polyunsaturated fatty acids. They are commonly used as biomarkers for oxidative damage, to assess in vivo lipid peroxidation in diseases related to the vascular system and neurodegeneration. Currently, there is a mismatch with the outcome in the use of these biomarkers in intervention studies, particularly when testing the effect of antioxidants such as vitamins C and E, or zinc, or a cocktail of these, with other food components. Much of this is because the biomarkers, the method of measurement, and the duration of supplementation are unsuitable. In this review, we will highlight the formation of isoprostanoids from their respective fatty acids, and their application as biomarkers for oxidative damage in vivo, considering human dietary intervention studies evaluating plasma and urine, using mass spectrometry techniques.
Subject(s)
Antioxidants/therapeutic use , Diet , Dietary Supplements , Isoprostanes/metabolism , Mass Spectrometry , Oxidative Stress/drug effects , Animals , Biomarkers/metabolism , Chromatography, Liquid , Diet/adverse effects , Gas Chromatography-Mass Spectrometry , Humans , Isoprostanes/blood , Isoprostanes/urine , Lipid Peroxidation/drug effects , Mass Spectrometry/methods , Nutrition Assessment , Nutritional Status , Oxidation-Reduction , Predictive Value of Tests , Tandem Mass Spectrometry , Treatment OutcomeABSTRACT
Perfluorooctane sulfonate (PFOS), a member of the perfluorinated chemical family, has been convincingly demonstrated to affect lipid metabolism in animals and humans and readily crosses the placenta to exert its effects on the developing fetuses. While its exact mechanism is still not clear, PFOS exposure has long been suggested to exert its toxicity via oxidative stress and/or altered gene expression. Levels of PFOS and malondialdehyde in various organs and cell cultures have been widely determined as general indicators of non-specific lipid peroxidation after PFOS exposure. In this study, the oxidation of precise polyunsaturated fatty acids and their metabolites, derived from enzymatic and non-enzymatic pathways was determined following PFOS exposure in both adult and maternal/fetal mice. CD-1 mice were exposed to 3 mg/kg body weight/day of PFOS in corn oil by oral gavage until late gestation (GD17). We demonstrated that lipid peroxidation was particularly and exclusively affected in fetuses exposed to PFOS, but this was not the case in the maternal mice, where limited effects were observed in the enzymatic oxidation pathway. In this study, we demonstrated that PFOS-induced lipid peroxidation might have a greater impact in free radical generation in fetuses than in dams and could be responsible for affecting fetal development. In addition, antioxidant enzymes, such as superoxide dismutase and catalase, appeared to maintain oxidative stress homeostasis partially in adult mice exposed to PFOS. Taken together, our results might elucidate the mechanism of how PFOS induces oxidative stress in vivo.
Subject(s)
Alkanesulfonic Acids/toxicity , Environmental Pollutants/toxicity , Fluorocarbons/toxicity , Lipid Peroxidation , Oxidative Stress , Prenatal Exposure Delayed Effects/metabolism , Animals , Catalase/metabolism , Cholesterol/blood , Fatty Acids, Unsaturated/blood , Female , Fetal Development/drug effects , Liver/enzymology , Mice , Organ Specificity , Pregnancy , Prenatal Exposure Delayed Effects/chemically induced , Superoxide Dismutase/metabolismABSTRACT
Isoprostanoids and isofuranoids are lipid mediators that can be formed from omega-3 and omega-6 polyunsaturated fatty acids (PUFAs). F2-isoprostanes formed from arachidonic acid, especially 15-F2t-isoprostane, are commonly measured in biological tissues for decades as the biomarker for oxidative stress and diseases. Recently, other forms of isoprostanoids derived from adrenic, eicosapentaenoic, and docosahexaenoic acids namely F2-dihomo-isoprostanes, F3-isoprostanes, and F4-neuroprostanes respectively, and isofuranoids including isofurans, dihomo-isofurans, and neurofurans are reported as oxidative damage markers for different metabolisms. The most widely used samples in measuring lipid peroxidation products include but not limited to the blood and urine; other biological fluids, specialized tissues, and cells can also be determined. In this review, measurement of isoprostanoids and isofuranoids in novel biological samples by gas chromatography (GC)-mass spectrometry (MS), GC-MS/MS, liquid chromatography (LC)-MS, and LC-MS/MS will be discussed.
Subject(s)
Biomarkers/analysis , Furans/analysis , Isoprostanes/analysis , Lipid Peroxidation , Oxidative Stress , Chromatography, Liquid , Gas Chromatography-Mass Spectrometry , Humans , Tandem Mass SpectrometryABSTRACT
BACKGROUND: A full-text search tool was introduced into the daily practice of Léon Bérard Center (France), a health care facility devoted to treatment of cancer. This tool was integrated into the hospital information system by the IT department having been granted full autonomy to improve the system. OBJECTIVES: To describe the development and various uses of a tool for full-text search of computerized patient records. METHODS: The technology is based on Solr, an open-source search engine. It is a web-based application that processes HTTP requests and returns HTTP responses. A data processing pipeline that retrieves data from different repositories, normalizes, cleans and publishes it to Solr, was integrated in the information system of the Leon Bérard center. The IT department developed also user interfaces to allow users to access the search engine within the computerized medical record of the patient. RESULTS: From January to May 2013, 500 queries were launched per month by an average of 140 different users. Several usages of the tool were described, as follows: medical management of patients, medical research, and improving the traceability of medical care in medical records. The sensitivity of the tool for detecting the medical records of patients diagnosed with both breast cancer and diabetes was 83.0%, and its positive predictive value was 48.7% (gold standard: manual screening by a clinical research assistant). CONCLUSION: The project demonstrates that the introduction of full-text-search tools allowed practitioners to use unstructured medical information for various purposes.
Subject(s)
Health Records, Personal , Hospitals , Information Storage and Retrieval , Medical Records Systems, Computerized , Biomedical Research , France , Humans , Internet , Qualitative Research , Search Engine , User-Computer InterfaceABSTRACT
Xenogenic fetal neuroblasts are considered as a potential source of transplantable cells for the treatment of neurodegenerative diseases, but immunological barriers limit their use in the clinic. While considerable work has been performed to decipher the role of the cellular immune response in the rejection of intracerebral xenotransplants, there is much still to learn about the humoral reaction. To this end, the IgG response to the transplantation of fetal porcine neural cells (PNC) into the rat brain was analyzed. Rat sera did not contain preformed antibodies against PNC, but elicited anti-porcine IgG was clearly detected in the host blood once the graft was rejected. Only the IgG1 and IgG2a subclasses were up-regulated, suggesting a T-helper 2 immune response. The main target of these elicited IgG antibodies was porcine neurons, as determined by double labeling in vitro and in vivo. Complement and anti-porcine IgG were present in the rejecting grafts, suggesting an active role of the host humoral response in graft rejection. This hypothesis was confirmed by the prolonged survival of fetal porcine neurons in the striatum of immunoglobulin-deficient rats. These data suggest that the prolonged survival of intracerebral xenotransplants relies on the control of both cell-mediated and humoral immune responses.
Subject(s)
Antibodies, Anti-Idiotypic/immunology , Cerebral Cortex/immunology , Graft Rejection/immunology , Immunoglobulin G/immunology , Neurons/immunology , Transplantation, Heterologous , Animals , Antibodies, Anti-Idiotypic/pharmacology , Cells, Cultured , Cerebral Cortex/cytology , Cerebral Cortex/surgery , Flow Cytometry , Graft Rejection/metabolism , Graft Rejection/pathology , Graft Survival , Immunoenzyme Techniques , Neurons/cytology , Neurons/transplantation , Rats , Rats, Inbred Lew , SwineABSTRACT
The oxidative stress (OS) hypothesis is able to explain several features of Rett syndrome (RTT), a pervasive development disorder almost exclusively affecting females mainly caused by a mutation in the X-linked methyl-CpG binding protein 2 (MeCP2) gene. In particular, the generation of an OS imbalance is related to MeCP2 gene mutation type, as well as natural history, clinical heterogeneity of the disease, and is compatible with the potential reversibility of the disease observed in the RTT animal models. In addition, our findings indicate the importance of blood as a suitable biological fluid for detecting markers of central nervous system oxidative damage in RTT and underline the key role of interaction between organic chemists, OS biochemists, and clinicians in revealing potential new markers of the disease and identifying potential new targets and interventional strategies aimed at improving the quality of life of these patients, affected by a so far incurable disease. Further efforts in the near future are needed in order to dissect the "black box" of the molecular events likely linking the MeCP2 gene mutation to OS derangement and subsequent disease expression.