Search results for " Albumin"
showing 10 items of 320 documents
Lead(II) ions adsorption onto amyloid particulates: An in depth study
2022
The production of new cost-effective biocompatible sorbent sustainable materials, with natural origins, able to remove heavy metals from water resources is nowadays highly desirable in order to reduce pollution and increase clean water availability. In this context, self-assembled protein materials with amyloid structures seem to have a great potential as natural platform for a broader development of highly-tunable structures. In this work we show how protein particulates, a generic form of protein aggregates, with spherical micro sized shape can be used as adsorbents of Pb2+ ions from aqueous solution. The effect of pH, ionic medium, ionic strength and temperature of the metal ion solution…
Myoglobin on Silica: A Case Study of the Impact of Adsorption on Protein Structure and Dynamics
2013
International audience; If protein structure and function changes upon adsorption are well documented, modification of adsorbed protein dynamics remains a blind spot, despite its importance in biological processes. The adsorption of metmyoglobin on a silica surface was studied by isotherm measurements, microcalorimetry, circular dichroïsm, and UV-visible spectroscopy to determine the thermodynamic parameters of protein adsorption and consequent structure modifications. The mean square displacement and the vibrational densities of states of the adsorbed protein were measured by elastic and inelastic neutron scattering experiments. A decrease of protein flexibility and depletion in low freque…
Thermal aggregation of bovine serum albumin at different pH: comparison with human serum albumin.
2007
We report here a study on thermal aggregation of BSA at two different pH values selected to be close to the isoelectric point (pI) of this protein. Our aim is to better understand the several steps and mechanisms accompanying the aggregation process. For this purpose we have performed kinetics of integrated intensity emission of intrinsic and extrinsic dyes, tryptophans and ANS respectively, kinetics of Rayleigh scattering and of turbidity. The results confirm the important role played by conformational changes in the tertiary structure, especially in the exposure of internal hydrophobic regions that promote intermolecular interactions. We also confirm that the absence of electrostatic repu…
Organometallic Palladium Complexes with a Water-Soluble Iminophosphorane Ligand As Potential Anticancer Agents
2012
The synthesis and characterization of a new water-soluble iminophosphorane ligand TPA=N-C(O)-2BrC(6)H(4) (C,N-IM; TPA = 1,3,5-triaza-7-phosphaadamantane) 1 is reported. Oxidative addition of 1 to Pd(2)(dba)(3) affords the orthopalladated dimer [Pd(μ-Br){C(6)H(4)(C(O)N=TPA-kC,N)-2}](2) (2) as a mixture of cis and trans isomers (1:1 molar ratio) where the iminophosphorane moeity behaves as a C,N-pincer ligand. By addition of different neutral or monoanionic ligands to 2, the bridging bromide can be cleaved and a variety of hydrophilic or water-soluble mononuclear organometallic palladium(II) complexes of the type [Pd{C(6)H(4)(C(O)N=TPA-kC,N)-2}(L-L)] (L-L = acac (3); S(2)CNMe(2) (4); 4,7-Diph…
Modulation of protein tyrosine nitration and inflammatory mediators by isoprenylhydroquinone glucoside.
2007
The nitration of tyrosine caused by peroxynitrite and other reactive nitrogen species is clearly detrimental for some physiological processes; however, its signalling role is still open to controversy. Among the natural phenolics known for their ability to oppose free tyrosine nitration, isoprenylhydroquinone glucoside is investigated due to its unusual structure, which contains a simple hydroxybenzene alkylated by a hemiterpenoid moiety. This hydroquinone was shown to be an effective inhibitor of peroxynitrite-induced protein tyrosine nitration in 3T3 fibroblasts. When tested on bovine seroalbumin nitration, however, the potency was reduced by half and the effect was almost abolished in th…
New functional ligands for ficolin-3 among lipopolysaccharides of Hafnia alvei.
2011
Ficolin-1 (M), ficolin-2 (L), ficolin-3 (H) and mannan-binding lectin (MBL) activate the complement system and have opsonic activity. The specificity of ficolin-3 is poorly characterized and currently limited to a few ligands only. We present new specific targets for human ficolin-3, identified among lipopolysaccharides (LPSs, endotoxin) of Hafnia alvei. The interaction was restricted to LPSs of four strains: 23, Polish Collection of Microorganisms (PCM) 1200, PCM 1203 and PCM 1205 and limited to their O-specific polysaccharides (O-specific PSs) composed of different numbers of oligosaccharide (OS) repeating units (RUs). Moreover, these LPS/ficolin-3 complexes activated the lectin pathway o…
Interaction of dicaffeoylquinic derivatives with peroxynitrite and other reactive nitrogen species.
2008
Plant phenolic antioxidants, among them catechins and hydroxycinnamoyl conjugates, constitute a well defined class of inhibitors of reactive nitrogen species (RNS). To gain deeper insight in this field, we examined the effects of 3,5-di-O-caffeoylquinic acid (DCA), its methyl ester (DCE) and epigallocatechin gallate (EGCG) in nitrative and oxidative processes. These compounds were found to be strong inhibitors of the nitration of tyrosine residues induced by ONOO- in bovine seroalbumin, with their IC50 values (10-40 microM) notably decreasing in the presence of bicarbonate. When studied on the intracellular protein tyrosine nitration induced by ONOO- in cultured murine fibroblasts as well a…
Long-term albumin administration in decompensated cirrhosis (ANSWER): an open-label randomised trial
2018
Background Evidence is scarce on the efficacy of long-term human albumin (HA) administration in patients with decompensated cirrhosis. The human Albumin for the treatmeNt of aScites in patients With hEpatic ciRrhosis (ANSWER) study was designed to clarify this issue. Methods We did an investigator-initiated multicentre randomised, parallel, open-label, pragmatic trial in 33 academic and non-academic Italian hospitals. We randomly assigned patients with cirrhosis and uncomplicated ascites who were treated with anti-aldosteronic drugs (≥200 mg/day) and furosemide (≥25 mg/day) to receive either standard medical treatment (SMT) or SMT plus HA (40 g twice weekly for 2 weeks, and then 40 g weekly…
Predictors of serious adverse events and non-response in cirrhotic patients with primary biliary cholangitis treated with obeticholic acid
2022
Background & Aims Obeticholic acid (OCA) has recently been restricted in patients with primary biliary cholangitis (PBC) with "advanced cirrhosis" because of its narrow therapeutic index. We aimed to better define the predicting factors of hepatic serious adverse events (SAEs) and non-response in cirrhotic patients undergoing OCA therapy. Methods Safety and efficacy of treatment were evaluated in a cohort of consecutive PBC cirrhotic patients started with OCA. OCA response was evaluated according to the Poise criteria. Risk factors for hepatic SAEs and non-response were reported as risk ratios (RR) with 95% confidence intervals (CIs). Results One hundred PBC cirrhotics were included, 97…
Is Transient Elastography Needed for Noninvasive Assessment of High-Risk Varices? The REAL Experience
2019
INTRODUCTION: The Baveno VI consensus guidelines and an expanded algorithm suggest that transient elastography (TE) and platelet (PLT) count can be used to identify patients with cirrhosis who can avoid esophagogastroduodenoscopy (EGD). The primary aims of this study were to assess the ability of a simple algorithm, which uses only laboratory parameters, to predict medium/large esophageal varices (EV) in patients with hepatitis C virus (HCV) and cirrhosis from the Rete Sicilia Selezione Terapia-HCV (RESIST-HCV) cohort and to compare the performance of the algorithm with Baveno VI and Expanded Baveno VI criteria. The secondary aim was to assess the role of TE in ruling out large EV. METHODS:…