Search results for "carbohydrates"
showing 10 items of 474 documents
Development of antibiotic loaded biodegradable matrices to prevent superficial infections associated to total knee arthroplasty.
2019
Abstract Development of a pharmaceutical form for the superficial infections related with arthroplasties would be helpful for clinical practice. In this context, we set out to evaluate ciprofloxacin and gentamicin elution from systems based on chitosan. Films and semisolid hydrogels containing chitosan alone (2%) or in combination with gelatin (6%) or different proportions (from 12% to 36%) of tetrakis-(hydroxymethyl)-phosphonium-chloride (THPC) were tested as delivery systems. Different antibiotic doses were assayed (0.5 mg/cm2,1 mg/cm2 and 2 mg/cm2). Antibiotic release was studied for each formulation. In vitro cytocompatibility studies and a simulation exercise for bioactivity evaluation…
The shell matrix of the freshwater mussel Unio pictorum (Paleoheterodonta, Unionoida). Involvement of acidic polysaccharides from glycoproteins in na…
2007
13 pages; International audience; Among molluscs, the shell biomineralization process is controlled by a set of extracellular macromolecular components secreted by the calcifying mantle. In spite of several studies, these components are mainly known in bivalves from only few members of pteriomorph groups. In the present case, we investigated the biochemical properties of the aragonitic shell of the freshwater bivalve Unio pictorum (Paleoheterodonta, Unionoida). Analysis of the amino acid composition reveals a high amount of glycine, aspartate and alanine in the acid-soluble extract, whereas the acid-insoluble one is rich in alanine and glycine. Monosaccharidic analysis indicates that the in…
Stability and disassembly properties of human naïve Hsp60 and bacterial GroEL chaperonins.
2015
Human Hsp60 chaperonin and its bacterial homolog GroEL, in association with the corresponding co-chaperonins Hsp10 and GroES, constitute important chaperone systems promoting the proper folding of several mitochondrial proteins. Hsp60 is also currently described as a ubiquitous molecule with multiple roles both in health conditions and in several diseases. Naïve Hsp60 bearing the mitochondrial import signal has been recently demonstrated to present different oligomeric organizations with respect to GroEL, suggesting new possible physiological functions. Here we present a combined investigation with circular dichroism and small-angle X-ray scattering of structure, self-organization, and sta…
Combination vaccines containing DTPa–Hib: impact of IPV and coadministration of CRM197 conjugates
2008
Vaccination with diphtheria-tetanus-acellular pertussis (DTPa)-Haemophilus influenzae type b (Hib) combinations generally elicits anti-polyribosyl-ribitol-phosphate (PRP) antibody concentrations of more than 0.15 microg/ml, a criterion that is linked to the protection of infants against Hib disease. In the UK, vaccination with DTPa3-Hib elicited atypically low anti-PRP antibody levels and was associated with breakthrough Hib cases. While the absence of a toddler booster is considered to be a key factor explaining the lowered control of Hib disease, we propose that the coadministration of serogroup C Neisseria meningitidis conjugate vaccine (MenC)-CRM197, which coincided with the introductio…
The Role Played by Ionic Liquids in Carbohydrates Conversion into 5-Hydroxymethylfurfural: A Recent Overview
2022
Obtaining industrially relevant products from abundant, cheap, renewable, and low-impacting sources such as lignocellulosic biomass, is a key step in reducing consumption of raw fossil materials and, consequently, the environmental footprint of such processes. In this regard, a molecule that is similar to 5-hydroxymethylfurfural (5-HMF) plays a pivotal role, since it can be produced from lignocellulosic biomass and gives synthetic access to a broad range of industrially important products and polymers. Recently, ionic liquids (ILs) have emerged as suitable solvents for the conversion of biomass and carbohydrates into 5-HMF. Herein, we provide a bird’s-eye view on recent achievements about t…
Chemical Pretreatments of Wood Chips Prior to Alkaline Pulping - A Review of Pretreatment Alternatives, Chemical Aspects of the Resulting Liquors, an…
2015
The chemical industry is being forced to evaluate new strategies for more effective utilization of renewable feedstocks to diminish the use of fossil resources. In this literature review, the integration of both acidic and alkaline pretreatment phases of hardwood and softwood chips with chemical pulping is discussed. Depending on the pretreatment conditions, high-volume sulfur-free fractions with varying chemical compositions can be produced. In case of acidic pretreatments, the major products include carbohydrates (mono-, oligo-, and polysaccharides), whereas under alkaline (i.e., aqueous NaOH) pretreatment conditions, the sulfur-free fractions of aliphatic carboxylic acids, lignin, and ex…
Cytochrome-P450 phosphorylation as a functional switch
2002
Xenobiotic metabolizing cytochromes P450 (CYP) were shown to be phosphorylated in vitro (using purified protein kinases together with purified CYPs), in intact cells (in V79 cells after transfection of cDNAs coding for individual CYPs, in diagnostic mutants, in hepatocytes), and in whole organisms (rats). CYP phosphorylation is highly isoenzyme selective in that only some CYPs are phosphorylated. Protein kinase A (PKA) was identified as a major catalyst for the phosphorylation of CYPs. The PKA recognition motif Arg-Arg-X-Ser is present in several members of the CYP2 family, but is used by only some of them, most notably by CYP2B1/2B2 and CYP2E1. For CYP2B1 it was shown that a substantial po…
A Review on Molybdenum Determination in Solid Geological Samples
2007
This review highlights the necessity for the development of proper sampling and storage, fast pretreatment methodology followed by highly sensitive detection for the determination of molybdenum in geological samples. Distribution of concentration and chemical speciation of molybdenum analysis in solid geological matrices have also been discussed.
Properties and significance of apoFNR as a second form of air-inactivated [4Fe-4S]·FNR of Escherichia coli
2005
The active form of the oxygen sensor fumarate nitrate reductase regulator (FNR) of Escherichia coli contains a [4Fe-4S] cluster which is converted to a [2Fe-2S] cluster after reaction with air, resulting in inactivation of FNR. Reaction of reconstituted [4Fe-4S].FNR with air resulted within 5 min in conversion to apoFNR. The rate was comparable to the rate known for [4Fe-4S].FNR/[2Fe-2S].FNR cluster conversion, suggesting that apoFNR is a product of [2Fe-2S].FNR decomposition and a final form of air-inactivated FNR in vitro. Formation of apoFNR and the redox state of the cysteinyl residues were determined in vitro by alkylation. FNR contains five cysteinyl residues, four of which (Cys20, Cy…
Phosphorylation of the Goodpasture antigen by type A protein kinases.
1995
Collagen IV is the major component of basement membranes. The human alpha 3 chain of collagen IV contains an antigenic domain called the Goodpasture antigen that is the target for the circulating immunopathogenic antibodies present in patients with Goodpasture syndrome. Characteristically, the gene region encoding the Goodpasture antigen generates multiple alternative products that retain the antigen amino-terminal region with a five-residue motif (KRGDS). The serine therein appears to be the major in vitro cAMP-dependent protein kinase phosphorylation site in the isolated antigen and can be phosphorylated in vitro by two protein kinases of approximately 50 and 41 kDa associated with human …