Aromatase in the brain of teleost fish: expression, regulation and putative functions.

International audienceUnlike that of mammals, the brain of teleost fish exhibits an intense aromatase activity due to the strong expression of one of two aromatase genes (aromatase A or cyp19a1a and aromatase B or cyp19a1b) that arose from a gene duplication event. In situ hybridization, immunohistochemistry and expression of GFP (green fluorescent protein) in transgenic tg(cyp19a1b-GFP) fish demonstrate that aromatase B is only expressed in radial glial cells (RGC) of adult fish. These cells persist throughout life and act as progenitors in the brain of both developing and adult fish. Although aromatase B-positive radial glial cells are most abundant in the preoptic area and the hypothalamus, they are observed throughout the entire central nervous system and spinal cord. In agreement with the fact that brain aromatase activity is correlated to sex steroid levels, the high expression of cyp19a1b is due to an auto-regulatory loop through which estrogens and aromatizable androgens up-regulate aromatase expression. This mechanism involves estrogen receptor binding on an estrogen response element located on the cyp19a1b promoter. Cell specificity is achieved by a mandatory cooperation between estrogen receptors and unidentified glial factors. Given the emerging roles of estrogens in neurogenesis, the unique feature of the adult fish brain suggests that, in addition to classical functions on brain sexual differentiation and sexual behaviour, aromatase expression in radial glial cells could be part of the mechanisms authorizing the maintenance of a high proliferative activity in the brain of fish

Genomic expression and single-nucleotide polymorphism profiling discriminates chromophobe renal cell carcinoma and oncocytoma

<p>Abstract</p> <p>Background</p> <p>Chromophobe renal cell carcinoma (chRCC) and renal oncocytoma are two distinct but closely related entities with strong morphologic and genetic similarities. While chRCC is a malignant tumor, oncocytoma is usually regarded as a benign entity. The overlapping characteristics are best explained by a common cellular origin, and the biologic differences between chRCC and oncocytoma are therefore of considerable interest in terms of carcinogenesis, diagnosis and clinical management. Previous studies have been relatively limited in terms of examining the differences between oncocytoma and chromophobe RCC.</p> <p>Methods</p> <p>Gene expression profiling using the Affymetrix HGU133Plus2 platform was applied on chRCC (n = 15) and oncocytoma specimens (n = 15). Supervised analysis was applied to identify a discriminatory gene signature, as well as differentially expressed genes. High throughput single-nucleotide polymorphism (SNP) genotyping was performed on independent samples (n = 14) using Affymetrix GeneChip Mapping 100 K arrays to assess correlation between expression and gene copy number. Immunohistochemical validation was performed in an independent set of tumors.</p> <p>Results</p> <p>A novel 14 probe-set signature was developed to classify the tumors internally with 93% accuracy, and this was successfully validated on an external data-set with 94% accuracy. Pathway analysis highlighted clinically relevant dysregulated pathways of c-erbB2 and mammalian target of rapamycin (mTOR) signaling in chRCC, but no significant differences in p-AKT or extracellular HER2 expression was identified on immunohistochemistry. Loss of chromosome 1p, reflected in both cytogenetic and expression analysis, is common to both entities, implying this may be an early event in histogenesis. Multiple regional areas of cytogenetic alterations and corresponding expression biases differentiating the two entities were identified. Parafibromin, aquaporin 6, and synaptogyrin 3 were novel immunohistochemical markers effectively discriminating the two pathologic entities.</p> <p>Conclusions</p> <p>Gene expression profiles, high-throughput SNP genotyping, and pathway analysis effectively distinguish chRCC from oncocytoma. We have generated a novel transcript predictor that is able to discriminate between the two entities accurately, and which has been validated both in an internal and an independent data-set, implying generalizability. A cytogenetic alteration, loss of chromosome 1p, common to renal oncocytoma and chRCC has been identified, providing the opportunities for identifying novel tumor suppressor genes and we have identified a series of immunohistochemical markers that are clinically useful in discriminating chRCC and oncocytoma.</p

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P &lt; 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Acid gelation of mixed thermal aggregates of pea globulins and β-lactoglobulin

International audienceThe acid gelation by glucono-delta-lactone of thermal protein aggregates from mixed pea globulin (Glob) and beta-lactoglobulin (beta lg), namely "mixed-aggregates", was investigated at 25 degrees C in comparison to that of mixtures of thermal aggregates of each protein obtained beforehand separately ("mixtures of aggregates"). A phase diagram indicating thermal gelation and acid gelation conditions was obtained from mixed protein systems varying in concentration and composition. The minimum acid gelation concentration was 3% regardless of the protein aggregates system, a value about half the concentration threshold measured for thermal gelation. The rheological properties, the microstructure and the water holding capacity (WHC) of acid gels were then evaluated from 4 wt% protein aggregate solutions at different beta lg/Glob weight ratios (0/100, 30/70, 50/50, 70/30 and 100/0). Acid gelation led to weak viscoelastic gels and the gel strength increased with beta lg content. The formation of acid gel from "mixed-aggregates" resulted in more elastic gels and improved WHC compared to gels resulting from "mixtures of aggregates". This behavior seemed to correlate with the regular filamentous and highly entangled gel network structure observed for mixed-aggregates. These properties were believed to originate from the initial structure of the thermal protein aggregates strongly influenced by beta lg content

1H NMR Spectroscopy As Tool To Study Transglutaminase Crosslinking Of Pea Globulin

Skiathos Island, GREECE - 30 May - 02 June 2013International audienceA new method based on NMR spectroscopy was developed to detect the G-L (GlutamylLysine) isopeptide bonds formed by the enzymatic transglutaminase reaction. Because of thecomplexity of NMR signals of proteins due to their structures, the method was first developedon a model system (glutamine and lysine) to simplify the detection of the G-L residue. Andthen, the results were applied on the real protein matrix (pea globulin). MTG treatment ofmodel system led to the appearance of a new resonance on NMR spectrum which isoriginated probably from the ε-methylene protons of lysine residues covalently linked toglutamine. The comparison between NMR spectra of MTG-treated and untreated pea globulinwith MTG-treated model system permitted to identify the G-L isopeptide signal. The G-Lisopeptide signal is also observed in the NMR spectra of native pea globulin (untreated whichMTG), indicating that the isopeptide is naturally present in pea proteins. However, thesuperimposition of NMR spectra of MTG-treated and untreated pea globulin shows a higherintensity of G-L isopeptide signal for MTG-treated samples. The increased signal intensityevidences the enzymatic reaction and permits to quantify the G-L isopeptide

Heat-Induced Soluble Protein Aggregates from Mixed Pea Globulins and β-Lactoglobulin

International audienceThe present work investigates the formation of protein aggregates (85 degrees C, 60 min incubation) upon heat treatment of beta-lactoglobulin (beta lg) pea globulins (Glob) mixtures at pH 7.2 and 5 mM NaCl from laboratory-prepared protein isolates. Various beta lg/Glob weight ratios were applied, for a total protein concentration of 2 wt % in admixture. Different analytical methods were used to determine the aggregation behavior of "mixed" aggregates, that is, surface hydrophobicity and also sulfhydryl content, protein interactions by means of SDS-PAGE electrophoresis, and molecule size distribution by DLS and gel filtration. The production of "mixed" thermal aggregates would involve both the formation of new disulfide bonds and noncovalent interactions between the denatured beta lg and Glob subunits. The majority of "mixed" soluble aggregates displayed higher molecular weight and smaller diameter than those for Glob heated in isolation. The development of pea whey protein "mixed" aggregates may help to design new ingredients for the control of innovative food textures

Molecularly imprinted sol-gel polymers for the analysis of iprodione fungicide in wine: Synthesis in green solvent

International audienceIprodione is a fungicide widely used in viticulture in most agricultural countries. It was banned recently in the European community because of its carcinogenic and endocrine disrupting characters. In this work, a cheap analytical method able to monitor iprodione in a white wine was developed. Molecularly imprinted sol-gel polymers (MIS) specific to iprodione and using green solvents were synthesized. An experimental design having the following factors (solvent volume and crosslinker quantity) was used to prepare an optimal MIS. In terms of selectivity, the optimal MIS showed the best partition coefficient towards iprodione in a white wine containing four other competing fungicides (procymidone, pyrimethanil, azoxystrobin and iprovalicarb). A solid phase extraction method using the optimal MIS was optimized and applied to analyse iprodione in a white wine. Low detection and quantification limits were reached 11.7 and 39.1 µg/L respectively

Préparation de liposomes fonctionnels pour l’encapsulation de composés bioactifs ou de sondes moléculaires fluorescentes pour l’imagerie cellulaire

International audienceAt ICMUB Institute, SUV liposomes have been used to achieve fluorophore encapsulation (subphtalocyanine) for cellular imaging [1] and have been bioconjugated to a peptide (bombesin) to achieve site-specificity, thanks to the structural modification of cholesterol, a component of the liposome, upon introduction of a reactive function. Hence, such liposomes fonctionnalised on the outer face may react with the terminal function of the peptide. Upon purification of the liposome by FPLC a 15 % encapsulation rate was measured by UV/Vis and attempted by ICP. The (outer) diameter of the liposomes (dDLS and dMET) ranged between 20 and 60 nm depending on the type of function or substituents on the outer face of the liposome [2]. Monitoring of the size and stability of the liposomes was achieved over time. This overall approach is also carried out at PAPC team (UMR PAM, AgroSup Dijon) to achieve the the conjugation of the liposome to proteins [3] (b-lactoglobuline) or polysaccharides [4, 5] (chitosan and pectin). The final aim will get functional and stable liposomes in different media. These nano-objects will be sub-mitted to several physical and chemical stress (pH, temperature, oxidation, etc.) and their strength will be analysed. Glutathione will be encapsulated inside the liposomes and used like molecular sensor for the determination of oxidized state medium. These systems will be also choice models for the study of behaviour of cell’s membrane.A l’Institut ICMUB, les liposomes SUV ont été utilisés pour l’encapsulation de fluorophores (sub phtalocyanine) pour l’imagerie cellulaire [1] et bioconjugués à un peptide (bombésine) en vue d’atteindre sélectivement une cible biologique. Ceci est réalisé grâce à la modification structurale d’un constituant du liposome, le cholestérol, par introduc-tion d’une fonction d’accroche. Les liposomes ainsi fonctionnalisés sur leur face externe peuvent alors réagir avec la fonction terminale du peptide. Après purification du liposome en FPLC, un taux d’encap-sulation de 15 % est mesuré par UV/Vis et estimé par ICP, et le diamètre (dDLS et dMET) est estimé entre 20 et 60 nm selon le type de fonction ou de groupement situé sur la face externe du liposome [2]. Un suivi dans le temps a été effectué pour examiner la taille et la stabilité des liposomes. La même approche est en cours pour la conjugaison des liposomes à des protéines [3] (b-lactoglobuline) et polysaccharide [4, 5] (chitosan et pectine) au sein de l’équipe PAPC (UMR PAM, AgrosSup Dijon). L’objectif à terme sera d’obtenir des liposomes fonctionnels et stables dans les différents milieu d’études. Ces nano-objets seront soumis à différents stress physicochimiques (pH, température, oxydation, etc.) et leurs resistances seront analysées. Le glutathion sera encapsulé dans les liposomes et servira de capteur embarqué pour determiner l’état d’oxydation du milieu. Ces systèmes constitueront également des modèles d’étude de choix pour mimer le comportement des membranes cellulaires

A micellar multitasking device: sensing pH windows and gauging the lipophilicity of drugs with fluorescent signals

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Monitoring of transglutaminase crosslinking reaction by 1H NMR spectroscopy on model substrates

International audienceA new method based on 1H NMR spectroscopy was developed for monitoring transglutaminase crosslinking reaction with model molecules (CBZ-Gln-Gly and N-α-acetyl-lysine). The transglutaminase reaction led to the appearance of new resonances on NMR spectrum as well as significant decrease in others. The new observed resonances, originated from newly formed ɛ-(γ-glutamyl)lysine isopeptide bonds, evidence the enzymatic reaction and allow to quantify the ɛ-(γ-glutamyl)lysine fragment. Moreover, the decrease in resonance intensity, originated from lysine, permit to determine the crosslinking degree. These results obtained by 1H NMR spectroscopy can be used as an alternative method to LC–MS, reducing drastically the analysis time from 7 days to 2 h