Laboratoire Of Biophysique

Paris, France

Laboratoire Of Biophysique

Paris, France
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Daroui-Mokaddem H.,University of Mentouri Constantine | Daroui-Mokaddem H.,Annaba University | Kabouche A.,University of Mentouri Constantine | Boutaghane N.,University of Mentouri Constantine | And 3 more authors.
Natural Product Communications | Year: 2017

One new flavonol glycoside, patuletin-7-O-[6-O-caffeoyl-2-O-[(S)-3-hydroxyisobutanoyl]glucopyranoside] (astermaritimoside) (1) and four known flavonoids, patuletin-7-O-β-[-6-O-[(S)-3-hydroxyisobutanoyl]glucopyranoside] (2), patuletin-7-O-[6-O-caffeoylglucopyranoside] (3), patuletin-7-O-β-Dglucopyranoside (4) and quercetin-3-O-β-rutinoside (5) have been isolated from Asteriscus maritimus (L.) Less. Chemical structures were elucidated by mass spectrometric, and 1H NMR,13C NMR, COSY, HMQC and HMBC spectroscopic techniques. The antioxidative effect was evaluated using an electronic spin resonance (ESR) method in order to visualize the inhibition of the DPPH radical. The n-butanol fraction was found to possess a remarkable antioxidant activity that was correlated with the total amount of phenolics. The isolated compounds exhibited good antioxidant activity.

Monde A.A.,Félix Houphouët-Boigny University | Kouame-Koutouan A.,Laboratoire Of Biophysique | Lagou D.A.,Service de nephrologie du CHU de Yopougon | Camara-Cisse M.,Félix Houphouët-Boigny University | And 4 more authors.
Medecine Nucleaire | Year: 2013

The chronic renal insufficiency is a frequent disease which has many biological consequences. It involves disturbances of the biological functions of the organization, among which variations of calcium, phosphorus and the parathormone during the IRC, object of this study. It acts of a descriptive cross-sectional study carried out in the service of medical biochemistry of the CHU of Cocody in collaboration with the service of nephrology of the CHU of Yopougon and having concerned 70patients. The results of this study were characterized by the relatively young age of the patients (on average 39. years) compared to the data of the literature (60. years and more), the male prevalence of the IRC (53%). We noted a prevalence of the IRC at the stages severe (27.14%) and terminal (51.43%). The disturbances of the metabolism phosphocalcic were marked by a hypocalcemy observed in 87.12% of the cases, making fear signs of osteodystrophy, a hyperphosphoremy in 51.43% of the cases and a secondary hyperparathyroid, in connection with the severity of the disease in 87.12% of the cases. A good monitoring is useful for chronic renal failure, very common in CÔte d'Ivoire, with prevention measures to avoid its occurrence. © 2013 Elsevier Masson SAS.

Mertes P.M.,French Institute of Health and Medical Research | Bazin A.,Caen University Hospital Center | Alla F.,University of Lorraine | Bienvenu J.,University of Lyon | And 8 more authors.
Journal of Investigational Allergology and Clinical Immunology | Year: 2011

These guidelines represent a consensus among experts on hypersensitivity reactions occurring after transfusion of blood components. They cover recognition, investigation, treatment, and prevention of such reactions. Implemented in France under the auspices of the French Medicines and Healthcare Products Regulatory Agency (AFSSAPS) and based on current knowledge, research, and experience, they aim to provide effective and easily teachable means of further improving the quality of hemovigilance databases, promote interest in this fi eld, and help identify possible mechanisms and at-risk patient groups © 2011 Esmon Publicidad.

Laggoune S.,University of Mentouri Constantine | Brouard I.,University of La Laguna | Leon F.,University of La Laguna | Calliste C.-A.,Laboratoire Of Biophysique | And 4 more authors.
Records of Natural Products | Year: 2011

Two sterols, stigmasterol (1) and β-sitosterol (2), two lignans, (+)-sesamin (3), new for the genus Stachys and (±)-paulownia (4), new in the Lamiaceae family, reported for the second time from a natural source, and one acetylated flavone glycoside isoscutellarein-7-O-(2"-O-6"′-O-acetyl-β-D-allopyranosyl-β-Dglucopyranoside (5), were isolated from the roots of Stachys mialhesi de Noé. Surprisingly, 3g of compound 5 are gathered from 5g of roots extract. The structures of compounds 1-5 were established on the basis of physical and spectroscopic analysis, and by comparison with the literature data. The free-radical-scavenging property of compound 5 was evaluated by the use of the ESR method in order to visualize the inhibition of the 1,1-diphenyl- 2-1picrylhydrazyl (DPPH) free radical. © 2011Reproduction is free for scientific studies.

Juillard A.,University of Lille Nord de France | Juillard A.,Lille University of Science and Technology | Falgayrac G.,University of Lille Nord de France | Cortet B.,University of Lille Nord de France | And 8 more authors.
Bone | Year: 2010

The aim of this study was to investigate molecular interactions between a bisphosphonate (BP), zoledronic acid, and bone tissue by the use of Raman microspectroscopy. In this way, samples of hydroxyapatite (HA), as a bone model, and Wistar rat femurs were soaking in zoledronic acid solutions. Sample surfaces were studied by Environmental Scanning Electron Microscopy and Raman spectroscopy. The amount of zoledronic acid incorporated onto the samples and the inorganic phosphate released in solution were determined by 31P NMR spectroscopy. Total carbonate content in solution was evaluated by inorganic carbon analyser. After impregnation new Raman bands with frequencies close to characteristic peaks of zoledronic acid (in particular phosphate moieties and imidazole ring of the R2 side-chain) were observed on both types of samples. Physico-chemical parameters of the bone were also significantly modified (P<0.0001). The mineral to organic ratio and the carbonate to phosphate ratio decreased and the crystallinity increased. Released inorganic phosphate and carbonate were detected in the solutions. The Raman shift of the bands corresponding to the phosphate groups and the imidazole ring of the BP highlight their implication in the binding to the mineral. The detection of released inorganic phosphate and carbonate in solution, the modifications of the mineral to phosphate ratio and the carbonate to phosphate ratio reveal that BP decrease the amount of inorganic phosphate and limit the dissolution of bone mineral. The increase of the crystallinity after BP binding shows a re-organisation of the lattice with a higher symmetry. Thus, it seems that zoledronic acid has an important contribution on the increase of crystallinity. The use of Raman spectrometry brings new and complementary information on the impact of zoledronic acid on bone composition at molecular level. Raman spectrometry could help to understand by which way BPs improve bone strength and decrease fracture risk. © 2010 Elsevier Inc.

Martin C.,Marseille University Hospital Center | Jacob M.,Ludwig Maximilians University of Munich | Vicaut E.,Laboratoire Of Biophysique | Guidet B.,Hopitaux de Paris | And 2 more authors.
Anesthesiology | Year: 2013

Background: The aim of this meta-analysis was to evaluate renal safety with the active substance of the latest generation of waxy maize-derived hydroxyethyl starch in surgical patients. The authors focused on prospective, randomized, controlled studies that documented clinically relevant variables with regard to renal effects of waxy maize-derived hydroxyethyl starch 130/0.40. Materials and Methods: The authors carefully searched for all available prospective, randomized studies and evaluated the greatest delta from baseline values in renal safety variables (serum creatinine values, calculated creatinine clearance, incidence of renal replacement therapy, and acute renal failure). The authors included 17 studies that analyzed patients (n = 1,230) undergoing a variety of surgical procedures. Results: For maximum serum creatinine values, the effect size estimate was 0.068 (95% CI =-0.227 to 0.362), P = 0.65. For calculated creatinine clearance values, pooled risk difference was 0.302 (95% CI =-0.098 to 0.703), P = 0.14. For incidence of acute renal failure, pooled risk difference was 0.0003 (95% CI =-0.018 to 0.019), P = 0.98. For incidence of renal replacement therapy, pooled risk difference was-0.003 (95% CI =-0.028 to 0.022), P = 0.85. Conclusions: The authors found no evidence for renal dysfunction caused by modern waxy maize-derived hydroxyethyl starch 130/0.40 in surgical patients. © 2013, the American Society of Anesthesiologists, Inc. Lippincott Williams & Wilkins.

Sahli I.S.,Laboratoire Of Biophysique | Bettaieb H.A.,Laboratoire Of Biophysique | Ben Abdallah A.,Laboratoire Of Biophysique | Bhouri I.,University of Monastir | Bedoui M.H.,Laboratoire Of Biophysique
5th International Conference on Image Processing, Theory, Tools and Applications 2015, IPTA 2015 | Year: 2015

The aim of this study is the detection and segmentation of microcalcifications in digital mammograms using multifractal analysis. To detect the suspicious Region Of Interest (ROI), containing anomalies, we propose to decompose the whole image into ROIs and compare the multifractal spectrums based on the q-structure functions of each one. The segmentation of microcalcifications consists of two steps. On the first step, we create an image denoted 'α-image'. This image is constructed using the singularity coefficient, deduced from multifractal spectrum. Then, in the next step, we enhance the visualization of microcalcifications by creating an image denoted 'f(α)-image' based on the global regularity measure of the 'α-image' spectrum. We investigated the robustness of our approach using a data set of mammograms from 'MiniMIAS' database. Results demonstrate the accuracy of our approach, which successfully detect and segment microcalcifications with irregular form and small size. © 2015 IEEE.

Pylouster J.,University Paris Diderot | Pylouster J.,Laboratoire Of Biophysique | Bornot A.,University Paris Diderot | Etchebest C.,University Paris Diderot | De Brevern A.G.,University Paris Diderot
Amino Acids | Year: 2010

α-Helical transmembrane proteins (TMPα) are composed of a series of helices embedded in the lipid bilayer. Due to technical difficulties, few 3D structures are available. Therefore, the design of structural models of TMPα is of major interest. We study the secondary structures of TMPα by analyzing the influence of secondary structures assignment methods (SSAMs). For this purpose, a published and updated benchmark databank of TMPα is used and several SSAMs (9) are evaluated. The analysis of the results points to significant differences in SSA depending on the methods used. Pairwise comparisons between SSAMs led to more than 10% of disagreement. Helical regions corresponding to transmembrane zones are often correctly characterized. The study of the sequence-structure relationship shows very limited differences with regard to the structural disagreement. Secondary structure prediction based on Bayes' rule and using only a single sequence give correct prediction rates ranging from 78 to 81%. A structural alphabet approach gives a slightly better prediction, i.e., only 2% less than the best equivalent approach, whereas the prediction rate with a very different assignment bypasses 86%. This last result highlights the importance of the correct assignment choice to evaluate the prediction assessment. © 2010 Springer-Verlag.

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