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Ruta B, Czakkel O, Chushkin Y, Pignon F, Nervo R, Zontone F, Rinaudo M. Silica nanoparticles as tracers of the gelation dynamics of a natural biopolymer physical gel. SOFT MATTER 2014; 10:4547-4554. [PMID: 24817660 DOI: 10.1039/c4sm00704b] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The gelation of methylcellulose in water has been studied by X-ray photon correlation spectroscopy, electrophoresis and rheological measurements by looking into the dynamics of silica nanoparticles as tracers in the polymer matrix. The temperature and scattering vector dependence of the structural relaxation time is investigated at the nanometric length scale during the formation of the strong gel state. We find a stress-dominated dynamics on approaching the gel state, characterized by a hyper-diffusive motion of the silica particles. These results support the idea of a unifying scenario for the dynamics of complex out of equilibrium soft materials.
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Rinaudo M, Quemeneur F, Dubreuil F, Fery A, Pépin-Donat B. Mechanical Characterization of Micrometric Chitosan-Coated Vesicle by Atomic Force Microscopy. INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION 2013. [DOI: 10.1080/1023666x.2013.842352] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Rinaudo M, Cobos-Trigueros N, Solé M, Castro P, Hernández C, Nicolas JM, Vila J, Morata L, Pumarol J, Soriano A, Mensa J, Martínez JA. Comparison of acquisition of resistant microorganisms and infections in critically-ill patients with and without malignancies. Minerva Anestesiol 2013; 79:1217-1228. [PMID: 23752716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
BACKGROUND Patients with malignancies are often considered at risk of acquiring infections by resistant or potentially resistant microorganisms (RPRMs). However, data supporting this contention is scarce. We have compared critically ill patients with haematological malignancies (HM), solid tumours (ST) and without cancer (NC) in terms of acquisition of RPRMs, infections and mortality. METHODS Observational, prospective cohort study of patients admitted to a medical intensive care unit (ICU). Swabbing of nares, pharynx and rectum, and culture of respiratory secretions were obtained within 48 h of admission and thrice weekly thereafter. Clinical samples were obtained as deemed necessary by the attending physician. Clinical variables, severity scores on admission and exposures during ICU stay were also collected. Multivariable logistic regression analysis was used to evaluate ICU mortality. RESULTS Out of 969 included patients 127 (13.1%) had HM and 93 (9.6%) had ST. Patients with malignancies were more frequently exposed to central venous catheterization, methylprednisolone, and any antipseudomonal antibiotic whereas they were less commonly exposed to invasive mechanical ventilation. Patients with HM were more often admitted with an infection. There were no differences among groups in terms of RPRMs acquisition during ICU stay or prevalence of ICU-acquired infections due to any microorganism, including RPRMs. Having a HM was an independent predictor of mortality regardless of APACHE II score. CONCLUSION Critically ill cancer patients did not show a higher rate of RPRMs acquisition nor ICU-acquired infections. Mortality was higher in the HM group and it was not accurately predicted on admission by APACHE II score.
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Cobos-Trigueros N, Rinaudo M, Solé M, Castro P, Pumarol J, Hernández C, Fernández S, Nicolás JM, Mallolas J, Vila J, Morata L, Gatell JM, Soriano A, Mensa J, Martínez JA. Acquisition of resistant microorganisms and infections in HIV-infected patients admitted to the ICU. Eur J Clin Microbiol Infect Dis 2013; 33:611-20. [DOI: 10.1007/s10096-013-1995-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Accepted: 10/07/2013] [Indexed: 11/29/2022]
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Denarie D, Rinaudo M, Thomas T, Paul S, Marotte H. AB0457 Longitudinal study of serum TNF alpha levels, infliximab, and antibodies to infliximab in rheumatoid arthritis. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2012-eular.457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Rinaudo M, Quemeneur F, Pépin-Donat B. Experimental Characterization of Liposomes Stabilized by Polyelectrolytes and Mechanism of Interaction Involved. INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION 2012. [DOI: 10.1080/1023666x.2011.621735] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Rinaudo M, Milas M, Bresolin T, Ganter J. Physical properties of xanthan, galactomannan and their mixtures in aqueous solutions. ACTA ACUST UNITED AC 2011. [DOI: 10.1002/masy.19991400113] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Roure I, Rinaudo M, Milas M. Viscometric behavior of dilute polyelectrolytes. Role of electrostatic interactions. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19961000604] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Jomotte Granger S, Lunel A, Rinaudo M, Doussin JF, Bryssine B, Massignon D, Piriou V. [A case of acquired deficit in factor XI revealed by haemorrhage after caesarean delivery]. ANNALES FRANCAISES D'ANESTHESIE ET DE REANIMATION 2009; 28:1030-1031. [PMID: 19944555 DOI: 10.1016/j.annfar.2009.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Rinaudo M, Quemeneur F, Pépin-Donat B. Stabilization of Liposomes Against Stress Using Polyelectrolytes: Interaction Mechanisms, Influence of pH, Molecular Weight, and Polyelectrolyte Structure. INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION 2009. [DOI: 10.1080/10236660903289623] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Rinaudo M, Kil’deeva NR, Babak VG. Surfactant-polyelectrolyte complexes on the basis of chitin. RUSS J GEN CHEM+ 2008. [DOI: 10.1134/s1070363208110455] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Gomez C, Rinaudo M, Villar M. Oxidation of sodium alginate and characterization of the oxidized derivatives. Carbohydr Polym 2007. [DOI: 10.1016/j.carbpol.2006.05.025] [Citation(s) in RCA: 259] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Rinaudo M, Desbrières J, Rochas C. Gel Permeation Chromatography of Polyelectrolytes. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01483918108059609] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Heyraud A, Rinaudo M. Carbohydrate Analysis by High Pressure Liquid Chromatography Using Water as the Eluent. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01483918008060186] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Rinaudo M, Roure I, Milas M. Use of Steric Exclusion Chromatography to Characterize Hyaluronan, a Semirigid Polysaccharide. INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION 2006. [DOI: 10.1080/10236669908009743] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Acedo-Carrillo J, Rosas-Durazo A, Herrera-Urbina R, Rinaudo M, Goycoolea F, Valdez M. Zeta potential and drop growth of oil in water emulsions stabilized with mesquite gum. Carbohydr Polym 2006. [DOI: 10.1016/j.carbpol.2006.01.016] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Valdez M, Acedo-Carrillo J, Rosas-Durazo A, Lizardi J, Rinaudo M, Goycoolea F. Small-deformation rheology of mesquite gum stabilized oil in water emulsions. Carbohydr Polym 2006. [DOI: 10.1016/j.carbpol.2005.11.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Venter JP, Kotzé AF, Auzély-Velty R, Rinaudo M. Synthesis and evaluation of the mucoadhesivity of a CD-chitosan derivative. Int J Pharm 2006; 313:36-42. [PMID: 16476531 DOI: 10.1016/j.ijpharm.2006.01.016] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2005] [Revised: 01/11/2006] [Accepted: 01/13/2006] [Indexed: 11/24/2022]
Abstract
Combining mucoadhesive characteristics of a biodegradable polymer such as chitosan with the potential to enhance drug release by increasing the solubility of poorly water-soluble drugs has great potential for pharmaceutical technology and drug delivery design. Polymeric delivery systems have been extensively researched in an attempt to achieve modified drug release. Cyclodextrins (CD) offer an alternative approach. These cyclic oligosaccharides have the ability to form non-covalent complexes with a number of drugs altering their physicochemical properties. In the continuing challenge to improve the properties of delivery systems, this paper focuses on the modification of chitosan by introducing beta-cyclodextrin and to test the mucoadhesive strength and inclusion properties of this synthesised cyclodextrin-polymer. beta-Cyclodextrin was successfully grafted onto a chitosan chain polymer with a cyclodextrin grafting yield of 7% and a CD-chitosan yield of 85%. Although the complexation of (+)-catechin by the grafted beta-CD was found to be about five times weaker than that by the beta-CD monoaldehyde and natural beta-CD, the inclusion properties of the chitosan-CD remain promising. The mucoadhesive properties of chitosan-CD were compared to that of pectin (reference) and the parent chitosan with the use of a tensile separation test. The chitosan-CD showed mucoadhesive strengths of 12% stronger than pectin, but 13.5% weaker than the parent chitosan. The synthesised chitosan-CD-polymer exhibits characteristics of a possible mucoadhesive drug delivery system with some inclusion properties from beta-cyclodextrin.
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Rinaudo M, Auzely R, Vallin C, Mullagaliev I. Specific Interactions in Modified Chitosan Systems. Biomacromolecules 2005; 6:2396-407. [PMID: 16153074 DOI: 10.1021/bm0580025] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This paper concerns the bulk and interfacial properties of a series of alkylated chitosans having different alkyl chain lengths grafted randomly along the main chitosan chain. Chitosan has a low degree of acetylation (5%); on chitosan derivatives, the role of the degree of grafting and of length of the alkyl chains are examined. The optimum alkyl chain length is C12 and the degree of grafting 5% to get physical gelation based on the formation of hydrophobic domains. The cross-linking is essentially controlled by the salt concentration: it is shown that 0.025 M AcONa is needed to screen electrostatic interchain repulsions. Hydrophobic interactions produce highly non-Newtonian behavior with large thinning behavior; this behavior is suppressed in the presence of cyclodextrins able to cap the hydrophobic alkyl chains. The interfacial properties of the chitosan derivatives were tested for the air/aqueous solution interfaces. Specifically, the role of their structure on the kinetic of film formation was examined showing that excess of external salt favors the stabilization of the interfacial film. The derivatives with a higher degree of substitution and longer alkyl chains are more efficient and give a higher elastic modulus compared to the model surfactant as a result of the chain properties.
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Rinaudo M. Advances in Characterization of Polysaccharides in Aqueous Solution and Gel State. POLYSACCHARIDES 2004. [DOI: 10.1201/9781420030822.ch8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Abstract
This paper concerns the influence of the chemical structure on the physical properties of some polysaccharides. Especially, we proposed to discuss the role of the substituents on these properties. In some cases, non-carbohydrate substituents play a minor role on rheological properties in the presence of a salt excess as shown on xanthan and succinoglycan. The rheology of aqueous solution of these stereoregular polysaccharides is controlled by the conformation (helical conformation) whose stability is not largely influenced by these substituents. On the other hand, the interaction between galactomannan and xanthan depends on the presence of acetyl substituents on xanthan but also on the xanthan conformation. However, for polymers such as gellan, XM-6 or BEC 1615, complete deacetylation induces the ability to form physical gels in given thermodynamic conditions. The presence of carbohydrate substituents or short side chains was also examined. Especially in the gellan family, the role of position of substitution (position 3 on the glucose unit C or position 6 on the A glucose) was presented. It is concluded that the substituents giving the higher stability for the helical conformation (higher DeltaH and Tm values) also cause a lower salt sensitivity for the helical stability. The role of the substituents on the properties is also described for natural polymers and their chemically or enzymatically modified derivatives.
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Dı́az-Rojas E, Pacheco-Aguilar R, Lizardi J, Argüelles-Monal W, Valdez M, Rinaudo M, Goycoolea F. Linseed pectin: gelling properties and performance as an encapsulation matrix for shark liver oil. Food Hydrocoll 2004. [DOI: 10.1016/s0268-005x(03)00085-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Haxaire K, Maréchal Y, Milas M, Rinaudo M. Hydration of polysaccharide hyaluronan observed by IR spectrometry. I. Preliminary experiments and band assignments. Biopolymers 2004; 72:10-20. [PMID: 12400087 DOI: 10.1002/bip.10245] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This article is the first one in a series dedicated to the study of hyaluronan as observed by IR spectrometry. The goal is to determine its hydration mechanism and the structural changes this mechanism implies. Hyaluronan is a natural polysaccharide that is widely used in biomedical applications and cosmetics. Its macroscopic properties are significantly dependent on its degree of hydration. In this article we record the IR spectrum of a several micron thick dried film and deduce that four or five residual H(2)O molecules remain around each disaccharide repeat unit in the dried film. We then compare the spectra of sodium hyaluronan and its acid form to assign vibrational bands linked to the carboxylate group. We proceed with a qualitative analysis of the spectral changes induced by changes of temperature and hygroscopicity, two independent parameters that act by modifying the hydrogen bond network of the sample. This enables us to assign most of the vibrational bands of the hydrophilic groups and to distinguish the bands that are due to these hydrophilic groups when they are or are not hydrogen bonded. It constitutes a prerequisite for the quantitative analysis of hydration spectra that will be described in the following articles of this series.
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